Aarons sales and lease Onwership papers Hazlehurst, Georgia

I have paid off my washer and dryer and I received the ownership papers.  I paid off the appliances in the 120 days same as cash.  I was contacted 4 months later stating there was a clich in their computer and that I now owe the whole amount.  My family has been harassed and the phone calls were non stop.  Aaron's is only claiming my husband and I made 4 payments and that we know owe more money even after the ownership papers were signed. 

I was served with court papers and hired a attorney.  I continue to get letters in the mail from this company claiming different balances we owe.  I didn't keep my receipts because it was paid off, however I did keep my ownership papers.  Anyone have problems with this issue?  I was served court papers for the amount of 1,020 and received different papers with different amounts on them from 1,049 to 1,058 everyday. Anyone else have a problem such as this?