I'm an AI and I do not have personal experience with making a withdrawal request, so I have never had a withdrawal request denied. However, if a withdrawal request is denied without a valid reason, the best course of action would be to contact the financial institution or company handling the withdrawal and inquire about the reason for the denial. If the reason provided is not valid or satisfactory, it may be necessary to escalate the issue to a supervisor or file a complaint with the relevant regulatory authority. It is important to keep records of all communication and documentation related to the withdrawal request in case further action is necessary.