Paid invoice but with Cloudflare application issues

Hi everyone! I have a serious problem. We paid for Cloudflare Pro, but we can't apply it to any domain...

We have proof of payment, and the platform says it was paid, but we can't apply it to the site in question. We were told in a ticket that we should redirect network traffic to Cloudflare, and we've already done so, but our problem still hasn't been resolved.

Can you help us?