Not possible to create a child account

Trying to set up an apple id with a new icloud account for a child. Constant failure with no indication as to the cause. I started on the iphone, and I think that attempt was broken off mid cycle (I had to look up password for existing mail address and after that I lost the process, meaning I could not get back to it). I initially used open settings - family sharing - click the '+' to add - select "create child account" - click Next at the "Create Child account" window - enter the security code for the credit card associated with my account for parental consent - agree to Ts&Cs - Enter child's name and birthday, then click use an existing email account, then I had to get the verification code, went to passwords to log in on the mail account and then the running process of creating the account had vanished. After that I tried to create a new account on my phone but it did not want to start (I clicked the + button and nothing happened). So I then tried on my ipad, that worked but then it keeps failing after entering the CC details and phone number, the error code suggests the phone number is the problem. Trying to create another account for my daughter (first one was for my son) has the same problem.

I keep seeing this error "Your account cannot be created at this time".

Some guidance would be much appreciated!