- Access your Mailbox settings from the Email Settings menu. Tap on the 'Three Bars' icon and 'Cog' icon afterwards.
- Tap on your account to access the sync settings
- Tap on 'Email Sync Period'
- Under 'Email Sync Period', change the period date from '3 Days' to 'All time'
- Once these steps are completed, tap on return until you are back in your Mailbox. It might take a few minutes for your inbox to finish synchronizing.