Lack of Efficiency, Transparency and Communication

My brother rented a vehicle with Avis as his car was going for repairs.Upon returning the vehicle there was no communication as to when the holding amount will be released. Weeks later, the deposit is still pending. Upon calling them their response is the account on the system is incorrect. Question is, why do you not call and seek the correct one. After giving them the account again, days still progress without any word from them once again. After calling them again and again being transfered to everyone the response is still the same, the account we have here is incorrect. After fixing that problem again don't know if their putting in the wrong digits in finance department they say it will take 6working days to resolve, previously they said 48hours.Hai maan...🧐