This one is on us, not you.
It means the security check we run during sign-up could not be reached. Nothing about your details is wrong, and there is nothing you can change to get past it.
Was my account created?
No. Sign-up stops before anything is saved. There is no half-made account, no email is sent, and your referral or sponsor code is not used up.
What to do
Wait a few minutes and try again from the start. It is usually brief.
Do not keep submitting the form. Repeated attempts do not get through any faster.
If it lasts more than about half an hour
Let us know through How to contact ClubAffili support, with roughly when you tried. It helps us match your attempt to what we can see on our side.
Is this the same as "the security check failed"?
No, and the difference matters. "Failed" means the check ran and did not pass — usually a browser extension or VPN, and there are steps you can take. See Why the security check keeps failing. "Temporarily unavailable" means it never ran, and only waiting helps.