Hi, I have this same issue. in this discussion: Plone 5.1 soft-released
they mention the same problem; however, in the problem description it is specified the person put in an email that didn't exist. in my case this is true - the user put in an email in the reset that didn't exist in the system.
i just did the same action you did: i sent a reset link. i don't know yet if it worked.