My Tmobile G1 is not saving contacts?

[Steve]

Every time I add a contact the phone will save it. When I try to add another contact, the phone will delete the previous contact and save the current one. I have asked around and no one seems to know what is going on. I also do not have a data plan for this phone.

 

[Unregistered]

same problem.. the other day i updated the program on my phone.. i dont have a data plan so my mms messaging wasn't working. but after i updated it... i could receive picture messaging! that only lasted like 2 weeks. but after i updated it... my contacts stopped saving.. its really frustrating!