Reset password not allowed

Had a user email to say they couldn’t log in. I checked, their account is there, all looks fine. They have one day to go before their listing expires [which is why they wanted to log in – to renew].
I got their user name and email address from the database. I clicked the new password button [front end], entered their email address and tried to send them a new password. I get the message:
Password reset is not allowed for this user

I updated the theme to the latest version last week.

Any ideas?