Hi! The best would be to post what steps you tried accompanied with screenshots/recordings in our official Discord server at https://discord.gg/dXez8Zh in the Extension Help channel so we can take a look at it for you.
Extension has not been migrated yet to the new OBSWS 5.0 (and OBS 28). This is a known issue which the website and its documentation is warning about as well. Please see here: https://sammi.solutions/docs/getting-started/step-by-step#installalldependencies