Hello!

I'm having an issue with the "Send mail as" option on Gmail. I am not receiving the confirmation email on my Zoho Mail account. A few days ago, it worked, then it stopped, and now when I try to fix it, I simply don't receive the confirmation email to finish the process. Just to clarify, Gmail can send the email to other Gmail accounts, but I never receive it on Zoho account...

What's going wrong? Is it Zoho's fault? Gmail's? It it my settings?