I got follow-borked twice in the last 24hrs. My suspicion it was an out-of-date app on my iPad. I removed and reinstalled. 

 Which one? 

 Old Damus iPad app. It kept asking me to add follows. 

 Which version are you on now? 

 1.9 (14) 5c3fc63c 

 Which other apps are you using with the keys?

Did you try the first aid in settings? 

 What iPad app you using I was trying for ages a year ago or so and could t get any to work 

 Damus. It works quite well!