Are the contact details you entered for GMail the same as those you entered for Apple? Same country?

Also, you do not belong to or reside in/didn't travel through any of the restricted countries, do you?

Just throwing some pointers out there. Hope you get it sorted out.

I have a suspicion it's because you setup the gmail account and the immediately linked it to another service. I did the same thing a few years ago where I was signing up for a service I didn't entirely trust. The new gmail is disabled by the end of the first day with the same vague message.

If I need to do that again I'll use a different email provider.

Ah the ~weekly don’t trust google reminder.

Hopefully the hn Helpdesk can assist