Hello, over 12 hrs ago someone bought some BTC of mine with Zelle. He hasn’t paid and isn’t responding in chat. It says Remaining time: 3 days, 15 hours under Trade Information. Do I really have to wait that long for a resolution?
Yes, at that time it will be possible for you to open mediation from the GUI.
https://bisq.wiki/Dispute_resolution
To favor security, Bisq trades aren’t very quick when a peer is not very cooperative.