Name changed in settings for mailbox but still not changed when typed in To field

Name changed in settings for mailbox but still not changed when typed in To field

In the email account secretary@ i have updaetd the new staff members details but the old members name still appears when I type secretary@ in the To field. I cant work out where Zoho is finding the old name from. I have deleted the browser cache. If I do the same thing in Apple Mail App the corrct name is used.

Please hekp!