Hello Yp8118,
Thanks for asking the Apple Support Communities for help with Apple Music and the alert shown in your screenshot.
1. I recommend force closing the Music app. How to force an app to close on your iPhone, iPad, or iPod touch - Apple Support
2. Then restart your iPhone. Restart your iPhone, iPad, or iPod touch - Apple Support
3 . If you still have trouble after restarting, I notice you are connected to a wireless network. I recommend trying while connected to a different wireless network. You can also try by turning off Wi-Fi and testing only with your cellular connection (if possible.)
- To turn Wi-Fi off and use your cellular connection, go to Settings > Wi-Fi, and turn the slider off. Be aware that this will use your cellular data until you turn Wi-Fi back on.
4. If you still have a problem, also check the troubleshooting in this help article: Get help with iCloud Music Library - Apple Support
Thanks and have a wonderful day.