One of my family member removed from family without any permission and can not come back

[memomat]

One of my family member removed from family without any permission. I sent her an invite but when she accapting the invite app transferring her to web site for filling an address form. After filled the form it says ''3 - Oops something went wrong, please try again.'' and she can not join the family account. I try to change web browser, clear the history, change the device and many other things but nothing works. Can anybody help?