At the time of rental, a pre-authorisation hold is secured on the credit card provided (debit cards are not allowed), to cover the estimated rental charges and any additional charges that may be incurred. A Pre-Authorisation is a blocked amount on the card limit, which may appear as a debit and will not be available for your use. The Pre-Authorisation amount is reduced from the total credit limit on your credit card but is not released to us. The pre-authorisation is released in the normal course as pre-defined by your respective banks. Additional pre-authorisations (holds) are be obtained if the vehicle is not returned on the date/time noted on the rental agreement or if the original terms of the rental change, which result in additional charges. A request for releasing a block on a credit card is forwarded by us as applicable but may take up to 21 working days to process in your account unless it is automatically released as per the set time period by your bank.