sorry the rule is you bid you win you pay
there are few acceptable reasons to retract changing your mind not reading the listings or buying same elsewhere are not among them and you could find yourself reported for invalid bid retraction if you wrongly retract. Retractions are noted on your profile and multiple retractions could see sellers blocking you
you should hope you are outbid or should you win pay and resell on ebay
not paying could find you with an unpaid item dispute and could count towards you being unable to bid on some items in the future

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