Never fully loads

For the last two months I have been trying to download yoga sessions (any yoga sessions), my Wi-Fi is working perfectly but the download always gets stuck, nor matter what session I chose or how big the download. I uninstalled and reinstalled the app, I turned my phone on and off, I signed out and back in but nothing works. I paid for a years premium membership to not be able to download yoga sessions... When it works, I love it, but Ive not been able to use this app in months.

WantsToDoYoga about FitStar Yoga, v1.2.1