I purchased Nintendo switch online and can no longer play local multiplayer on the same Nintendo switch console even though everything that game tells me is wrong, contradicts itself.

I recently purchased the Nintendo Switch Online for my Nintendo Switch. So, naturally, I log into Minecraft and I was waiting for my friends to join realms with me. While I was waiting I grabbed another one of my Nintendo switch pro controllers and handed it to my dad so we could play local multiplayer together. But when he tried to log in it said on his portion of the split screen that I need Nintendo online to play multiplayer (which I have) and that multiplayer is turned off (which it wasn't). So, now I can't even play local multiplayer on the same console.