To enable automatic updates of all apps from Google Play Store:
Open the Play Store app
Tap the profile icon at the top right
Select “Settings”
Select “Network Preferences”
Enable “Auto-update apps”
To only enable auto update for Softpay app:
Open the Play Store app
Tap the profile icon at the top right
Select “Manage apps and devices”
Select “Manage” tab
Tap the Softpay app icon to get to the apps “Details page”
Tap the icon with the three dots in the upper right corner
Enable “auto update”.