Please read the following steps to turn on dark mode for Microsoft Teams. If you follow these steps it should only take you 60 seconds.
Step 1.) Open Microsoft teams and look at the top right hand corner where it shows your online status. Click that once.
Step 2.) Click the “settings” option.
Step 3.) Up the top of the page you will now see an option to select dark mode. It will be between default and high contrast. Once you click dark mode it should auto save and apply that setting.