It is impossible to contact zoho support

It is impossible to contact zoho support

I register zoho mail service few days ago, sadly after used it for days, I am afraid it is not a right service for me. I would like to ask for a refund and cancel my account. I have been trying to reach your customer service by emailing cancellation@zohocorp.com and support@zohocorp.com but no one reply after 5 days, I called your customer service phone line, she barely spoke any english and hung up on me. This is getting annoying now. Can someone please take care of the case asap.