To do the firmware update manually:
- Download nRF Connect from Google Play Store https://play.google.com/store/apps/details?id=no.nordicsemi.android.mcp&hl=en&gl=US
- Download the this fw.zip file to your mobile
- Open nRF Connect. Tap "Scan" and allow permissions
- You will see a device named DFUTargXXXX (where XXXX are random numbers. Alternatively you can see SIQB or SIQBB), select "Connect" on that device
- Tap "DFU" and select "Distribution packet ZIP" from the list, then locate the previously downloaded fw.zip file on your mobile
- Pick the file from the list and tap "Open". The firmware update process will begin. Wait while the process has completed successfully.