In 1986 I paid off my son's school loan (~$3000). Got the paid-off paperwork and everything. Then in 2003, 17 years later, TWO different companies came after me, trying to garnish my wages for the same loan.
They could have cared less about my 'paperwork'. The bank in Indiana that made the loan had long since gone out of business, so they weren't any help.
Since I was working for a state agency at the time, I got them involved, and finally, after about 18 months, it was taken care of. But even then, they were actually able to grab a paycheck or two, which I finally got refunded.
It seems that when the bank went under, they were selling off anything and everything they could get a buck for, including paid-off loans, now marked 'in default'. I wasn't the only one. Home mortgages, car loans, construction loans, etc. All were up for grabs.
Wow, what a story. The slime balls were probably just hoping you’d pay to make it go away.