They do not provide sms/email with the cost of the...

They do not provide sms/email with the cost of the travel immediately after the end of the trip, we have to pay what the driver asks. They do not cash or online payments, so we do not have proof of payment. I had used the cab and paid money that the driver demanded, 5 days later I got an SMS from the cab service with the cost, which was much lesser than what I paid, I called them up and they sided with the driver even though I tried explaining, they gave my personal no to the driver who called me and spoke very unprofessionally. Since the payment was made in cash there was no proof. They said they will look into the matter and never reverted.
Piece of advice to anyone who wishes to use this cab service, do not use. They cheat you and make you look like the culprit.