HELP... contacts disapper!

[mandyhohope]

I've had my droid for just about a month and have just recently (within the last week) started having my first problem! I have no idea why but my contacts repeatedly disappear from my phone. I have to go back in and import them every time to get them back and after doing so I have to reset all the picture ID's and custom ringtone settings for each contact that I had set before. It seems that my facebook contacts stay intact but all my phone numbers, etc. that were transferred from my old phone (about 500 contacts) disappear... over and over and over again. It's happened about 10 times now I'd say. I'M REALLY frustrated!
ANY IDEAS WHAT IS WRONG OR HOW TO FIX IT???
Mandy:icon_evil::motdroidhoriz: