Nearables Android SDK: background scanning

I reused the code from the demo app to scan for nearables. Additionally, I added a service to perform a scan in the background.

When service is running in the background it is logging the data into a file. Works fine.
Then, while the service is running, I start the GUI to visualise the nearables (the same code from the demo app), it works fine, but the service stops to log data into a file. The service is still running but not logging anymore. I need to restart the service…
I log each time onNearablesDiscovered() is triggered.

Also, do you maybe know, why I don’t see any log in the logcat from the Service?
The code is running on a Watch and I use Android Studio. The logs from Activities are visible.

Thanks in advace!