mpx220 problems

[Guest z1300]

hello, i hope some one can help. i have a mpx220. got it on a o2 contract and worked okay. but the better half couldnt get on with it, so got her a replacement.

ive bought a new o2 pay as you go sim and now it comes up sim card invalid or missing, tried it with my vodaphone sim and the same happens. ive tried a hard reset, still the same. any help would be apprecciated, ( any body want a mpx220 ) geof.