When bartering with Piglins, it seems causing an aggressive action will make them keep the gold while attacking you. I'm not certain what triggered this glitch, but I remember leaving the world in the middle of a barter, then coming back the next real-world day to continue playing. The Piglin will become uninterested in trading and attack the player (while keeping the gold indefinitely, those greedy guys).
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We're tracking this issue in MCPE-132380, so this ticket is being resolved and linked as a duplicate.
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