TMobile HTC m8 questions

[Gal Lapid]

Hi everyone,
I bought an HTC m8 a week ago from a store in ny.
The phone is TMobile branded and the store unlocked it for me with a code, so I could use it at my country with
the local carriers (im not an US resident).
Im having an issue with SMS messages being sent after 20-30 seconds, and MMS messages not being sent/received at all (I trired configuring
everything as the carrier instrcuted).
I wanted to Factory reset the phone, but after reading online I found out that factory reseting the phone will also mean the unlock code will disappear making my phone locked once again.

So, I have a couple of questions:
1. Is there a way to fix the SMS/MMS problems mentioned above without reseting the phone?
2. Will factory reseting my phone lock it again?
3. Will I be able to use the already used unlock code once again? If so, is there a way to extract the unlock code used at the store from the phone?

Thanks !

 

[Raymond Elliott]

A reset will not re-lock the phone. I reset my M7 before selling it and it did not loose the unlock.

As for MMS problem, all I can think of is your APN settings. Data is working fine, right?

 

[Gal Lapid]

A reset will not re-lock the phone. I reset my M7 before selling it and it did not loose the unlock.

As for MMS problem, all I can think of is your APN settings. Data is working fine, right?

Yes, Data works fine.

I didnt mention that I bought 2 phones from that store, one of which was factory unlocked, without any carrier branding.
The factory unlocked one works fine with MMS and Data, so i copied the same exact settings in the APN settings, but it didnt work... which makes me wonder
about the firmware/reset ...

Edit: Anyway, just to be on the safe side, Is there a way to get the code used to unlock the phone, so incase
it does reset I could unlock it once again ?