Airport Parking Assistance

I booked airport parking through The Parking Spot app for IAH July 12-26. Because of the CrowdStrike outages, we are getting back to IAH July 29. On the morning of July 12, there was no power at The Parking Spot. Everyone wi the reservations simply showed their app Rez to the staff and proceeded to park. However, that information is no longer in my app. And I have no proof of my reservation. I booked a discounted parking rez and am unsure of how to communicate all of this when I pay to leave. Any tips?