Cannot verify mobile number

Cannot verify mobile number

Dear Zoho support 
I need verify my domain, it's show: 

"This Domain is not supported or is already registered with Zoho" 


I was trying to verify my number , but i could not received number code to verify domain, after i refresh my browser and added domain again, i got the message " This Domain is not supported or is already registered with Zoho" and " this number is already register with Zoho" . Please advice me how to verify domain and add domain again.

My domain: yquizz(dot)com
Many Thannks,