Hi there! It sounds like you're having trouble with the Demus app on your iPhone (iOS 18.7), specifically when trying to log into your YouTube account and play songs. Just to clarify, when you say "he does ws" after logging in, could you please tell me more about what exactly happens? Are you seeing an error message, or does the app just freeze or crash?

Meanwhile, I can guide you through some common solutions that often help in situations like this:

1. Check Internet Connection: Ensure you have a stable internet connection, either Wi-Fi or cellular data. Sometimes streaming issues can happen if the connection is weak or unstable.

2. Log Out and Log Back In: Try logging out of your YouTube account inside the Demus app completely and then log back in. This can refresh the connection with YouTube servers.

3. Update the Demus App: Since you are using iOS 18.7, please confirm if your Demus app is up to date. Outdated apps can cause login and playback issues.

4. Reinstall the Demus App: Uninstalling and reinstalling the app can clear any corrupted temporary files that may prevent login or music playback.

5. Check YouTube Account Permissions: Make sure the Demus app has permission to access your YouTube account. Sometimes, re-authorizing the app via your Google account settings can resolve this.

6. YouTube Premium Requirement: Some users have reported that playing music through Demus using YouTube requires you to have a YouTube Premium subscription. Do you by chance have a Premium account? If not, this might be why music doesn't play even after login.

7. Region Restrictions: There are reports that Demus or certain YouTube music content might not be available in all regions. Could you please tell me your location or the region your account is set to?

If you've already tried any of these steps, please let me know which ones so I can suggest further troubleshooting. Also, feel free to share any error messages or behaviors you observe when you log in.

Looking forward to helping you get your music playing smoothly again!