We received a bill for a school loan 25 years after the loan was taken. We were certain that we paid off all school loans years ago. However, we began paying them $50 per month. But after reading some of these posts I'm not sure we did the right thing. I requested proof of the loan and never received it. The original loan amount was @800. but now is up to @$4000. Any ideas on how I should handle this situation?