If you experience problems with push notifications on a Samsung device, please perform the steps listed for your operation system:
Disable Battery Optimization
Remove Threema from Sleeping Apps
Disable Auto Optimization
Disable “Adaptive Battery”
Disable “Switch to Mobile Data”
Disable Power Saving Mode
Disable Battery Optimization
Remove Threema from Sleeping Apps
Disable Auto Optimization
Disable “Adaptive Battery”
Disable “Switch to Mobile Data”
Disable Power Saving Mode
Disable Battery Optimization
Remove Threema from Sleeping Apps
Disable Auto Optimization
Disable “Adaptive Battery”
Disable Battery Optimization
Remove Threema from Sleeping Apps
Disable Auto Optimization
Disable “Adaptive Battery”
Future OS updates might reset these adjustments, and you might have to perform the steps listed above again.
Should the problem persist after you have completed the steps listed above, please follow the general troubleshooting instructions.