Thanks for the information here.
We've been passing along these reports to our team who's investigating this issue. I apologize for any delays—we're diligently working to get this addressed as soon as possible.
In the meantime, try this solution submitted by another user
"Try keeping your iPhone displaying the hotspot configuration screen (the one that shows your hotspot password) through the ENTIRE connection process."Feel free to let us know if that helps. We'll follow up directly if we need more information or details from there.
Roku Community Manager