Please make sure that your date and time settings are correct; if the date/time on an Android device is set incorrectly, Gmail personalization does not work.
Also, please make sure the below is set up that IMAP is enabled on your account and that IMAP settings are set so the 'Sent Mail”'folder is visible via IMAP.
To ensure IMAP is enabled for Gmail follow the steps below:
- Tap the settings app in the list of apps on your phone
- Click on 'Forwarding and POP/IMAP' section
- In 'IMAP Access' section, click on 'Enable IMAP' radio button
- Click save changes at the bottom of page
To ensure the sent mail folder is visible in IMAP:
- Click button with the cog in the top right to enter Settings pane
- Click on 'Labels' section
- For the 'Sent Mail' label, make sure the checkbox 'Show in IMAP' is selected