The help file for servelink is here https://servelink.com/clients/index.php?rp=/knowledgebase/17/How-do-I-configure-my-ecommerce-template-store-e-mail.html
If you still have problems it might be worth asking there if your settings are correct.
It had to do with passwords. They put both of my domains in one account.
So each time I set my password for orders@ironmongeryonline.co.za it reset the password for orders@bathroomware.co.za
So how I got around it I created new email address to use in the control panel for each and each with different prefixes. And forward those emails onto my other email addresses.
It is a round about way but has solved the problem.