Hello every1

Topic's title already explains the problem. I just startet with Zoho Mail and only have 1 contact in my address book so far. This contact has 3 different mail addresses. But though I saved this contact in my contact list, mails from him always land in my spam folder. That's quite annoying, 'cause I don't see his mails, when I synchronize on my mobile. Any idea to solve this problem?

Thanks in advance