Hi there airforce653,
If the Apple Music app is freezing unexpectedly, you'll want to start by making sure your iPhone is updated to the latest iOS version, which is iOS 15.5. You can check that in Settings > General > About. Learn more about updating your iPhone here if needed: Update your iPhone, iPad, or iPod touch
If your iPhone is updated, and you're still seeing this behavior, we'd like to learn more to see how we can help. Are you streaming music or playing content that's downloaded on your iPhone? Does this happen with a specific playlist or album?
Also, what do you see when accessing Playing Next?
1. Tap the song that's playing at the bottom of your screen.
2. In the lower-right corner of your screen, tap Playing Next .
This link provides more information about how Playing Next works: Add music to your queue to play next on your iPhone, iPad, iPod touch, or Android device
Send over these details, and we'll take a closer look from there.
Cheers!