Hello Everyone, we are experiencing this same problem recently and could not come up with a solution. Basically the problem is that when autofill password is enabled and the same for the option in the preference to save the security password via iCloud we have the same problem posted by the OP in this thread:
https://developer.apple.com/forums/thread/716589?login=true&page=1#744911022
After filling the password field when we move to our confirm password field, the iOS system shows the same action sheet attached from the OP (String password or Other Options) and if we choose the Other Options action and then Choose My Own Password both field (Password & Confirm Password) will be emptied.
We have already tried the suggestions provided in the thread linked above but nothing seems to work.
Is this a normal behavior and we as engineers have the responsability to cache the password typed by the user when dealing with iCloud security password & autofill password preferences options or is this a strange behavior?
Thank you everyone for the time, if you have any further question don't esitate to ask