A dentist sent a bill to collections that is from 7/11/03.(my last date of service at which time I paid with a credit card,the total amount ask for. I didn't receive another bill for over 9 months when I tried to call them 8 different times but could never get to talk to the person in carge of billing.they were either out of the office or left me on hold for over 10 minutes.finally I gave up.but I didn't pay them as I think it is a mistake.has the statute of limitation run out( in calif)

It is 4 years, but the SOL would only come into play if they try to sue you. A debt never expires. The SOL only comes into play to prevent legal action.