Problem with MX Record Setting

Problem with MX Record Setting

I'm desperately trying to get my emails set up with Zoho but I keep getting bounced between my host and Zoho, each one seems to refer me to the other to get it  fixed.

I've tried all the different MX settings including "@" and domainname.co.uk in the name section in my DNS Manager (it won't allow a "blank" setting.

I can send emails from my Zoho account but cannot receive.

Anyone any idea how I can get this fixed? 

I'm using it for a small business I am running so if I can't resolve it I'll be binning my host and Zoho. Hopefully this won't be necessary.