Hello mariozs,
Thanks for using Apple Support Communities. We understand that the Music widget doesn't appear as expected on your iPhone. You've come to the right place! We're happy to help.
If you haven't already, restart your iPhone. Restarting is a simple step that can resolve many unexpected behaviors.
Restart your iPhone
Also, make sure that your iPhone has the latest software.
Update your iPhone, iPad, or iPod touch
Let us know the results. Be sure to include any other troubleshooting steps that you may have tried.
Have a great day!