Hello NJMoser,
It sounds as though your Powerbeats Pro pair successfully to your iPhone and Mac, but when paired with your iPhone you're not getting any audio. We're glad you had the opportunity to pair and test your Beats with your Mac, and determine the Beats are working as expected. This helps rule out any hardware issues with your Powerbeats Pro.
To confirm, since noticing this issue when paired with your iPhone, have you tried adjusting the volume when playing video or audio content? If not, make sure the volume is turned up either by using the Volume Up button on the left side, or in Control Center by swiping down from the top-right corner of the display, the drag the Volume slide up or down. These steps can also be found in the following articles.
If your headphones don't work with your iPhone, iPad, or iPod touch
Access Control Center on your iPhone and iPod touch
If you already have audio playing when pairing or connecting your Powerbeats Pro to your iPhone, it is possible that the audio content is being paused. You may have to tap the play icon after connecting your Beats.
Let us know how that goes!