I have also had this issue - I did a couple things to work around it:
1. I made sure I was connected to at least one of the same relays as the person I was trying to follow.
2. I downloaded both primal and plebstr and experimented with following there - plebstr seems to be most reliable for following, but it also blocks my zaps (says ‘not supported on iOS’) so I end up using multiple clients.
These are common software growing pains and will get resolved quickly, so it’s good to report issues like this with tags like you did here. 🤙
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