Cant add agent because he was added as a user

Cant add agent because he was added as a user

I added one of guys on as a user to test the customer portal. Now I cant add him as an agent because " Zoho Support ID already exists. Please use a different Zoho Support ID." I also cant delete him because he was added as portal user. I tried calling you support number and was told support is unavailable. 

This is not acceptable.