Avis Charge for unauthorized extra day

I booked a car online for 9:00 on 28 March for pick up at the Vereeniging branch that had to be returned the following morning at 9:00 to the same branch. I went early to collect the car to ensure there is enough time to do the inspections etc so that I could leave on time. I was helped earlier than expected and the inspection went quickly meaning the car was ready before 9:00. I was given the keys and told everything is fine for me to go. I returned the car the following day @ 9:12 (high traffic) and as they have a 29min grace period didn't think much of it further. When I received my Invoice a few days later I was billed for 2 days. not just that, they automatically added insurance and everything else without me signing an updated contract. Their reason is the following: The car was taken earlier than 9:00 and therefore the return time was moved earlier. Now no staff member mentioned this and explained that if I left a bit earlier that it would affect the time the car had to be back. If I knew this I would have waited for the few minutes as it would have been impossible for me to be back in time the next day.

Firstly, I feel it is unfair to bill us for the 2nd day if we did not know that the returning time was earlier. Secondly, if I was informed upon returning the vehicle of the situation I would at least have had the use of the vehicle for the second day I'm forcefully paying for. This leads me to think 2 things, either the staff was not doing their job to inform me the customer of these things or they did it on purpose, the paid for car was available for them to rent out again meaning they could potentially commit ***** by renting it out to someone else earning double the money. I mailed Avis about this and got the following response:

Good day, Philip,

Thank you for your email and apologise for the delayed response.

Rental ref: E ********** 90 Please be advised that as per the signed agreement, the vehicle supposed to be returned at the same time of collection. However Avis gives a 29 grace period, should the client return the vehicle after the grace period an additional will be charged. Kindly find the attached signed agreement.

Hope the above finds you well and your support is highly appreciated.

Kind Regards

Xolani Klaas

They just ignored everything I said and took the money regardless. I think it is highly unprofessional for them to do this and wonder how many unsuspecting costumers end up paying for an extra day without a valid reason. This also allows staff to easily commit ***** and should be investigated.