Use the physical navigation buttons to navigate to Settings > System > Touch Calibration to realign the digitizer. To help tailor this guide, please let me know: What is your current firmware version ?
The digitizer calibration data was wiped during the reset.
⚠️ Installing the wrong firmware (e.g., for Philadelphia 835S or 835DAB) will permanently brick your unit. Only use official Blaupunkt files matched to your exact hardware revision.