Unable to listen to music on my hearing aids connected to my iPhone XR

I have an iPhone XR I can connect the Bluetooth to my Phonak Audeo Lumity L90-R. I can use the myPhonak App. but when I try to listen to Amazon Music the sound comes out of the phone speakers. I can connect Skull Candy wireless ear buds and the music works just fine. I can connect my laptop to the hearing aids no problem watching YouTube. I just can't get the music to my hearing aids.

[Re-Titled by Moderator]