If you are perhaps not receiving some of your emails via your email program e.g. Outlook, this might help you.
You need to log into your webmail mail.your-own-domain.co.za (e.g. mail.theflowershopcpt.co.za) using your email and email password. 
Then you need to go to the Junk folder, all those emails are considered Junk by the server. If the emails you are looking for is in the Junk folder you need to drag the emails that you need to your Inbox (those emails will then come through to your computer as normal emails). Then under settings -> spam -> address rules, you need to add the email addresses you want to receive emails from (those that were listed under Junk), so that it doesn't land in Junk folder again. Choose Accept Mail From, add the email account and save. These marked addresses will then go directly to your inbox from hereon out. (See Screenshot)