Once you put a player on Auction, he will be available for the following 48 hours. There is no option to change the waiting time. You will get a notification about the outcome, but as it happens in football, some players need more time and others need less time to be transferred.

If your player is not sold after 48 hours, try a different strategy! It is possible that he was not the best fit for other Managers on the current transfer market or that his selling price was not appropriate for his quality and talent. Adjusting the price to your player’s quality can increase the chance of selling him and it can attract new bidders.