1) Click on Services in your Customer Zone

 

https://s3.amazonaws.com/cdn.freshdesk.com/data/helpdesk/attachments/production/33025198926/original/agzJW6trSL9-otT7-FUGU3BuYJLTLA4FUQ.png?1557231903

 

2) Click on Manage Product next to the service you wish to access.

 

https://s3.amazonaws.com/cdn.freshdesk.com/data/helpdesk/attachments/production/33025198935/original/jjEcxxa4ugdwUOV2XZEobxBUlSq9d0Felw.png?1557231909

 

3) Finally, click on Login to Control Panel to access your domain management interface.

 

https://s3.amazonaws.com/cdn.freshdesk.com/data/helpdesk/attachments/production/33025198937/original/fmYksfkRAjaM4U2zWA20gNoyvDzcR7nfEw.png?1557231914

 

4) Click on Mail and Accounts

 

 

 

5) Click on the email account

 

 

6) Enter the desired limit in MB