8210 problems... :(

[xJPx]

ok i have been given an old 8210 in pretty good condition..
i have been told it cuts out of calls but havent experienced it yet, tho i make small calls..

2nd problem an its the biggest i unlocked it using a code generator and have put in a new o2 sim card.. the phone boots up with orange software then
it will show BT CELLNET as operator but in a matter of seconds it turns off
when i insert an orange sim its perfect... any ideas ?

has it been ulocked using the wrong code ?
could it have had a poor flash/upgrade ?

any help will be greatly appreciated!!

[Mardu]

Correct me if I'm wrong, but I think Orange modded their phones' software to work only with their SIM cards. So, you possibly need to reflash the phone with a normal flash.