Received a collection letter from this Agency back...

Received a collection letter from this Agency back in 2010 requesting payment for around 30000 dollars for a bill that was payed by my insurance. I called and spoke with them after confirming with my insurance company that they had paid the bill. The agency rep was polite and stated that they indeed had received confirmation of payment and no further action would be taken. About 5 years later, I receive a summons stating I am being sued by this agency on behalf of the hospital for the same debt. I called the agency and attempted to explain that this was already taken care of. I was told they had no record of this, the debt had been confirmed by the hospital, and that they would continue with action unless I agreed to pay. I called the hospital myself at that point and spoke to their billing department who stated to me the bill was marked as paid in full and that they had no record of any action being taken against me and would contact the agency and stop any action. Very shady considering the summons named a billing representative from said hospital as verifying the debt. Either this agency does not keep up to date records despite placing current dates on items, or is scamming people. Either way, a huge headache for no reason and representatives that have no interest in actually hearing what you have to say. Could have been easily fixed by accepting my proof of payment, but apparently were more interested in forcing a lawsuit over nothing. Whole situation was very shady.