Family account problem

[Davidfa]

We have a spotify family premium and my father who is 84 did not notice that he had an email to reconfirm his email adress. No idea why he would recieve this email again only 1 month after the last lot of automated emails. 

anyway the problem is he never replied within 7 days and his part of the family account has been demoted to free. Not too great when he listens via alexa...

I have sent him an invite and helped him to accept it but the acceptance page keeps throwing up error 3 when the "oops something went wrong".