help with debrand g502 (uk)

[jasonx1]

hi i just been given a sony ericsson g502 on the three network (uk) which is unlocked but i have been using the three sim that was in it but the phone crashes a lot and the settings dont work good on othere sims like 02 ect thats why i want to debrand or is it worth just selling it on

can i debrand this phone to get rid off the three network rubbish
and still have the call and end buttons working

and is it possible i can have vodafone firmware or a firmware that will work better on a asda mobile sim which is a vodafone network partner

thank you

ps the firmware is r1fa037

[jasonx1]

the info is this on the a2 uploader

ChipID:C900,EMP protocol:0401

PHONE STATE: "RETAIL"
FLASH CID: 0052
OTP LOCKED:1 CID:52 PAF:1 IMEI:354xxxxxxxxxxxxxx CERT:RED

Model:G502
MAPP CXC article: R1FA037 prg12040015_HUTCHISON_EM
MAPP CXC version: R1FA037
Language Package:HUTCH-WORLD
CDA article: 1209-4467
CDA version: R9A
Default article: 1203-9948
Default version: R1FA037

Operator: 000-00

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