Hello,
Please tell us what the problem is in more details. Do you get any error messages, if yes what are they?
Doze Mode is where Android will not let apps run in the background as often as they need to while the phone is stationary.
The app will prompt you to “whitelist” (exclude) it from this “Doze Mode” within a day after installing if it detects Android 6 or newer.
To check, please bring up AquaMail settings -> mail, receiving.
If the app is not already whitelisted, there will be a green panel / button / message / prompt asking you to do this.
If you still have problems, please e-mail us at support@aqua-mail.com
Thanks,
Nadia