When I click on a station calling CQ POTA, WSJT-X changes the receive frequency to the station but does not change the TX frequency as well like it does with other stations that aren’t calling CQ POTA.
You should select "TX Hold", keep your transmit frequency in the audio bandwidth and call the station you want to contact.
Don't jump about following the TX frequency of the stations you want to contact, it's not necessary and you run the risk of taking over the audio frequency of the station that you just worked.