SSI, absolutely not. SSDI, maybe. You should've dealt with this in 2015, of course. First by going to the hearing, and secondly by requesting a waiver (based on your income and situation) within a few days of being notified of the overpayment. But that ship has long ago sailed.
Even though this was a non fraud overpayment, and it was not your fault you were first given it and then determined ineligible in a later decision, it happens, in times of low unemployment, and with that super belligerent right wing governor and legislature they have in place in KY right now, they may be pushing the ol' collection envelope for all programs. Have you received new information about this overpayment recently? If so, by all means, I encourage you to call them back, speak with someone, discuss your circumstances, etc. and try to see what you can work out with them. If you refuse to communicate, that causes them to push a lot harder, make a lot more collections efforts.
Though you really didn't do anything wrong by receiving these payments and usually these types of overpayments payments are not run down and aggressively collected on like the fraud overpayments are, they can, actually attempt to try to collect from you. But when they find that you are receiving SSI, if that is what it is, their collection efforts will cease. With SSDI, they might try and succeed at a garnishment. Hopefully, you didn't draw too many weeks before the second decision and there shouldn't be any penalties involved so maybe you don't owe much.