I wouldn’t waste the time with that “fix.” It sounds like they are grasping at straws!
1st: not everyone backs up to iCloud and you’ll Probably end up finding out that you have more than 5 gigs worth of back up, which means they’re going to try to encourage you to purchase more gigs, so they’re going to end up selling you more gigs to purchase and convince you that you need to back everything up in iCloud, which you don’t.
And what does resetting your phone have to do with pinning a message? That really males no sense that you have to “reset” your phone just to make their updates work right!
It’s a glitch, they know it, and there’s probably not much they can do about it until it’s fixed. The glitch only seems happens to group chats that contain android users, from the comments I have been seeing.
What I also noticed is that for me, if nobody has commented in the group chat in a 24 hour time frame it drops from pinned, but as soon as someone comments it reappears in the pins again. Which indicates that it’s an obvious glitch and is capable of being pinned with android users in the chat.
I’m pretty sure apple does not read any of these user support comments so we probably should start lodging complaints to them so that they can figure out that it is a real glitch that they need to fix.