Incorrect argument for command

Hello, everybody. I was hoping you could help me with a problem I've been running into with my server. So I created a server yesterday on 1.18.1 and for some reason I cannot make myself or my friends OPs. I type our names in but everytime I refresh they are gone. After that I tried making ourselves OPs using the console but I realised that the console wasn't working properly itself. The only command that managed to work using the console was "Time Set Day". So in my server I can't use commands in game or through the console and I can't make people OPs.

Wow, that was very simple. Thanks man.