Showing error MM#6

[Erlens]

I've been using my Xperia for a year (bought brand new), but today I've received message MM#6 and can't use phone! I've been reading forum and did what experts told to do (remove SIM, restart, even reset to factory mode), but still showing the same message! What should I do?

[owloap23]

got the same exact problem on my XA1 plus. I bought my phone a month ago. it was perfectly fine over the past few weeks and suddenly yesterday my sim1 (SMART Prepaid-PH) started to display the same exact error. I was not able to make outgoing calls and text message ( not to mention that I was also unable to receive incoming calls and text) but mobile data still works. I tried another sim card from the same exact network but still got the error. other network (GLOBE Telecom-PH) works fine (can make outgoing calls and texts as well as receiving incoming ones.

[Digiboom]

The MM#6 is a common thing when you are just swapping cards. What happens is the phone and sim don't register as being connected by the same provider 👨🏾‍💻🤷🏾‍♂️ it happened too me.. All I did was take it too the phone store and get it transferred to that provider.. And it worked fine... Still does  😊👍 using it to make this reply