Sure, we can take a closer look. Just to confirm, are you referring to the Primal iOS app? Note that we don't have a "follow back" button (we always display "follow"). Also, did you lose your entire follow list or just the last follow action didn't persist?  

 Yes Primal iOS. And yes, the follow action didn't persist. I did lose about half of my follow list around the same time (that's what prompted the testing) but not sure if it's related.