Afni review: cingular

What is it with CINGULAR I just got a bill from this collection saying I owe Cigular $65.95 but, afni Balance due $75.84. I had Cigular about 8 years ago I had settled out. Then year later a different collection angcy saying I owed them money it seem every year or so collections are saying I owe them money which now AT&T own them now. I;m getting really tired of these collections. The bad thing about this they like to wait a few years and scare you then you can't find your proof cause it was missed placed then when you call the company you had paid to the can't open your file. How can you put, a stop to this hassle? Thanks, Paula