mx records bluehost

mx records bluehost

I'm having trouble getting through the MX records stage with bluehost.

The only domain I have an option of picking is my current one.
once I enter the "@", "14400", "mx" "mx.zohomail.com" and "10" I get an error message that says YOU MUST PROVIDE THE NAME OF THE OLD EXCHANGER.

Anyone know what I did wrong?