Same here - when I arrived at AGP to return the car, the guy took the key, but he did not have his usual handheld and did not even want to look at the car....
Since then the car shows as return overdue in the app.... I hope they get this under control - I have no proof I ever gave the car back and never received an invoice either.... will not be fun if they have a mess and decide they are going to invoice the entire car to me....