Thanks for that info and choosing the Apple Support Communities. If I understand correctly, you are unable to use the Podcast app on your iPhone. To help resolve your issue, please force close the Podcast app and restart your device as iOS clears cached data and does other system optimizations when you turn your device off and on.
Force an app to close on your iPhone, iPad, or iPod touch
Restart your iPhone, iPad, or iPod touch
Cheers!