I try to login to the mixo app on mac os x 15.7 and app 2.3.0 and I am unable to login to the app. Perfect login on chrome but it doesnt login on the app. I tried the auth code as well and that says it is not valid.

Sorry to hear that. Please try working through the list here:
https://www.mixo.dj/guides/login-issues

I tried all the things and already unintalled and reinstalled and all that stuff. I can login on the app on the phone, but not on the computer

There are no issues with login our side and it's working on your phone (which uses the same system), so this indicates an issue with your desktop computer.

Did you try turning off your firewall temporarily?

Are there any settings on your router that might be blocking traffic?

Is your computer clock 100% accurate (to the second)?

Maybe also try the logout here: https://www.mixo.dj/login-success then login again.