You cannot stop it.
All members have the opportunity to retract a bid before 12 hours from end of auction.
If a buyer wins and then wants to cancel, you have the opportunity to close an unpaid case and issue the buyer with a strike.
If you haven't, set blocks on your account to block non payers.
Select account, site prefs, buyer requirements. Show and edit to the right.
Set blocks and save.
To add, always list an auction with a start price you will sell at in case you only get one.
No reserves in most categories on eBay Aus.
