iHeartRadio App Not Working Right in CarPlay After iOS 15 Update

I already contacted iHeartRadio's support about this. But, I thought I would ask, here, to see if anyone could help.

The iHeartRadio app isn't working correctly in CarPlay since I updated my iPhone 12 Pro to iOS 15. When I open the app, I just see a blank screen on my vehicle's display.

If I ask Siri to play a station, it will do so and I'll, then, see an arrow in the upper right corner of the screen.

If I tap the arrow, I can bring up the screen that shows me what station is playing and I can control playback.

If I tap "Back", I just go back to the blank screen. Didn't have this issue with iOS 14. Anyone know what the problem could be or how to fix it?