If you are using Android 9, we would suggest taking the following steps, and then looking up the information for your specific phone.
- Go to Settings on your phone
- Select Apps & Notifications
- Tap Advanced
- Select Special App Access
- Select Battery Optimisation
- Tap Zombies, Run! and switch to Not Optimised
Please also make sure that Background Restrictions are not enabled. To check this:
- Go to Settings
- Select Apps and tap on Zombies, Run!
- Tap on Advanced
- Select Battery
- Switch off Background Restrictions
For more information about battery optimisation, please read the main article.