401 message error

I’m getting this message ” 401
If you used authentication to add this domain, your API key may have been revoked. Please remove this domain and add it again.
Please read our guide for more details.”

I have removed and added domain and key 3-4times now and not working. I also clicked the button to receive a new key and doesn’t work that way either. My domain is very new and not had security set up yet so it shouldn’t be firewall?