Hey @Thomas_Birk, I have good news! My tablet has received a full system upgrade finally that has resolved the issue! It can connect to Wifi 6E again, just as before. Same AP, same SSID, it works...

@Thomas_Birk Did you find a solution to this problem? I have exactly the same issue. S8+ tab can't detect the 6GHz wifi that it used to connect to just fine. For me, the turning point was the OneUI...