Missing option to send activation email

I'm experiencing this problem:

"My customers are getting the error 'You are not authorized to access portal' - how can I fix this?"

https://support.freshdesk.com/support/solutions/articles/225303-my-customers-are-getting-the-error-you-are-not-authorized-to-access-portal-how-can-i-fix-this-

But, I do not have a "Send activation email" button against the contact in question.  Here are ALL the buttons I have:

Any suggestions as to what might cause this.  I need to get this customer allowed to log new tickets.

I am logged on as the "Account Administrator".

Many thanks