I am the maker of one of the BSQ offers you tried to accept. When you took the offer, I got a popup that said something like “the offer was blocked because the taker is blacklisted”, here’s the relevant part of the log file:
ERROR b.c.t.Task: An error occurred at task: ApplyFilter Other trader is banned by his node address. tradingPeerNodeAddress=<your onion address>
I also found your onion address in the thread about the recent SEPA chargeback scams:
So if you are not a scammer, you probably got blacklisted by mistake because your trading behaviour was similar to that of the scammer(s).
Whether or not you actually are a scammer, I find it pretty strange that the peers that got blacklisted for FIAT chargeback risk are also blocked from trading altcoins, as there is no chargeback risk there…