Is it normal for them to call a week after to close out a contract?

My car was in a hit and run and was being repaired through my insurance so they paid for a rental car for me through Enterprise. The way it worked is they dropped the car off at the repair shop for me and after it was done I dropped the car back off at the repair shop. I didn't interact with Enterprise beyond initially confirming the drop off date.
 
A week later, today, I've gotten a voicemail from them saying they want to talk to me about closing out the contract. They left the voicemail right before closing so by the time I called back they were closed and I have to wait until tomorrow to figure out why they are calling me. I am worried now about what this means. Does this mean they found damage on the car (it had some dings when I got it but I didn't document them so I'm worried what they will say) or is this standard when the rental went through insurance?