8 Quick Ways to Fix Phone Not Allowed MM#6

If you happen to have a used or refurbished smartphone that is linked or connected to a previous cellular company, you may see the “Phone not allowed MM#6” error every time you insert a SIM card.

This article will help you overcome the problem and resolve the error in different ways to see which works for you.

A lot of smartphone firms are releasing advanced and new smartphones, and many consumers are upgrading from old devices to new ones. These outdated devices are sold and reconditioned to individuals all around the globe.

However, refurbished devices are not brand new, which means that numerous software and parts are removed and replaced before selling to other people.

What Does Phone Not Allowed MM#6 Mean?

The “Phone not allowed MM#6” error appears if you try to send a message or make a phone call on a network-locked phone. It is the most common problem for those individuals who purchased a refurbished or a second-hand phone. Your phone may still be locked to a specific network carrier company.

phone not allowed mm6

It is very important to be meticulous when you are planning to buy a refurbished smartphone. There are also instances wherein the cellular carrier does not support the SIM card.

Network providers partner with smartphone firms to offer subscribers low-cost plans by locking the phone to that carrier. It ensures that it benefits both the network provider and the subscriber.

Users are confronted with the “Phone not allowed MM#6” issue because SIM cards from other network providers are prohibited. When AT&T customers try to utilize a MetroPCS SIM card for calling and messaging, they get this error code.

Why Does the Phone Not Allowed MM#6 Happen?

A lot of cellphone manufacturers partner with network carriers, and your phone will be locked to a specific network carrier. It helps the device manufacturer lessen their price while enabling the cellular carriers to have a lot of subscribers.

With this, your device can only work with one carrier, and you cannot have another SIM card. The “Phone not allowed MM#6” issue can be seen on Metro PCS, AT&T, other cellular carrier companies, and mobile manufacturers like Oneplus, Samsung, Huawei, Nokia, etc.

Network-locked phones are bound to a single service provider. Attempting to break this lock by inserting the SIM from another carrier is a terrible idea. The problem is most commonly seen on refurbished phones.

As previously stated, the issue can appear on unlocked devices at times. You may be dealing with a bug or a glitch. Updating the operating system typically helps.

Quick Ways to Fix the Phone Not Allowed MM#6 Error

When you get the “Phone not allowed MM#6” error while making or sending calls, it simply means your phone is tethered or locked.

We have several solutions to resolve this issue, but each works differently depending on the carrier.

1. Ask the Carrier to Unlock

A service provider that provides cellular connectivity is known as a carrier. To obtain EMI schemes, mobile companies form partnerships with these carriers. While there’s no assurance that the problem will be resolved right away, it’s worth a go.

You can call their toll-free numbers or email customer support with all necessary information regarding your issue. But, this process might become problematic;

  • If you’re dealing with a banned or a stolen phone, they may demand you complete specific standards before they can acknowledge your request.
  • For some phones, the operator may impose an “Equipment Switch” fee
  • For others, the devices may have an associated phone number. It will be challenging to have these phones unlocked.

For more details: How to Unlock Phone Free with IMEI?

2. SIM Unlocker

If you have a budget of up to $30, the SIM unlocker is a good option. Its allows you to utilize your smartphone on any carrier.

However, make sure the unlocker is the right one for your phone first. You must check for its compatibility.

If you are using an Android or iPhone device and have trouble with the error code, you should try a SIM Unlocker. It’s available in both online and offline technology stores. It will enable you to utilize your phone on any carrier network.

3. Dial Unlock Code *#78#

You can resolve this issue by dialing *#78#, It will take you to the operation menu, from which you can unlock your phone. However, there’s a possibility the number I gave you won’t work.

dial unlock code

This particular unlock code will vary based on the manufacturer and model of your phone. You might have to do conact carrier to get the network unlock code for your phone.

After that, you can disconnect from the cellular company, and your device will be unlocked. If you’re successful, you can utilize another SIM with your phone.

This option isn’t available with all carriers, so you’ll have to do some research online. Searching for your exact phone provider, brand, and unlocking choices will help you with what you’re doing.

4. Reinsert the SIM card

If the the above ways did not help you solve your problem, try a different approach. You can shut off your device before starting the steps.

Remove your phone’s SIM card and set it aside for 5 minutes. Reinsert your SIM card after you turn back on your device. Check if the MM#6 Error has reappeared.

5. Update Your Device

Since these phones are tied to a manufacturer or single carrier, it’s critical to keep your smartphone up to date to download and receive any software or security patches that could be triggering Error MM#6.

It’s simple to update your smartphone.

  1. Drag the notification panel to access your settings.
  2. Go to the bottom part and select Software Update or About phone.
  3. Select “Check for Updates”

samsung software update

If there are any updates that need to be done, tap the Install option and wait for them to finish installing.

Turn off your phone, insert your SIM card, and then turn it back on to check if the error message still pops up.

6. Automating network selection

There’s a good chance the “Phone not allowed MM#6” issue is caused by a poor or incorrect network selection.

  • Go to the notification panel’s “Settings” menu to resolve this issue.
  • Click “Connections” from the settings menu list. The option may be called something else on certain phones, such as “SIM Card And Mobile Networks.” Choose the relevant one based on your phone model.
  • Then look for and select the “Mobile Networks” option.
  • From the list, press “Network Operators,” choose your chosen network, and then tap “Select Automatically.”

android network selection automatic

After these steps, restart your phone to see if the problem has been resolved.

7. Wait for the SIM Activation Complete

If you’re having trouble with a new SIM, wait before trying again.

Activating a newly purchased SIM takes anywhere from 24 to 48 hours. Contact the carrier of your new SIM card of choice for further information on the activation process.

You must prove your identity for the operator to check the details regarding the activation of your new SIM card.

8. Contact Your Phone Manufacturer

If none of our suggestions work, the last option for resolving the “Phone not allowed MM#6” warning notice is to contact your phone manufacturer for assistance.

Contact them by phone or email and describe the problem without providing any personal information.

Inquiring for the company’s assistance is the most acceptable option because they will ensure that you follow federal and state laws. They’ll also figure out the best strategy to deal with the problem.

If You Don’t Know the Network You Phone is Locked to

You check the network carrier your iPhone is locked to with IMEI number. IMEI number contains critical information about your smartphone. This information allows network providers to trace or remotely turn off your device if it is stolen or reported lost.

It’s crucial to know the IMEI number of your phone, especially if you’re thinking about selling your phone or switching carriers. The IMEI number will ideally lead you to determine which cellular company you phone is locked to while fixing the MM#6 error.

The easiest way to check is via an accurate IMEI checker. You just need to submit the IMEI number, the IMEI checker will generate an IMEI report which contains all the information of your phone.

samsung att imei check


We hope this information has helped resolve your issue. To prevent the “Phone not allowed MM#6” error, we always recommend that you take precautions when buying a used device.

Purchase your used phone from a trustworthy service and ensure it is not associated with a carrier. If the different ways mentioned above did not work, it’s time to take your phone to a mobile repair shop near you.

I hope this post helped resolve your “Phone not allowed MM#6” problem. If a colleague or friend has trouble with this, recommend this article to help.

About the Author

Darren is an Apple Certified Independent Technician with a passion for researching all aspects of phone locks, including Activation Lock, carrier lock, screen lock, FRP lock, and more. With years of experience in the mobile phone industry, Darren has become a leading authority in his field and has been a sought-after consultant for individuals and businesses seeking to unlock their devices.

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