Hello, this was a T-mobile 6133 My Fav and it has a little water damage, but it still function most time, so I flash it with the same RM126 version, but at the end of the process when it shows pooling phone, the phone won't start back up, it only show the Nokia logo and turn off, so I tried with several different T-mobile files, they all the same, so I try the ATT file which is for 6126 RM126 and the process went fine, it restarted but with ATT logo and it won't accept AT&T Sim card, but it will take T-Mobile Sim card, now I connect to the BB5 box and thinking if I get it unlocked the logo makes no different, but the BB5 box showed model/version (4.28) not supported, please upgrade or downgrade, but whichever file that I flashed with will not complete the process when it reach Pooling phone, It will only completed with this ATT 4.28 file, my options are out, any one seen or heard this before? please help, I really appreciate and thanks in advance.