What is the phone, was the fingerprint at the back?
Given the information provided, it seems like you've already tried most software-related solutions. If the fingerprint sensor started malfunctioning right after a battery replacement, the issue is likely hardware-related.
- Recheck the Connections: During the battery replacement, a connection or cable related to the fingerprint sensor might have been accidentally loosened or disconnected. You might need to open the device again and check all the connections, especially those associated with the fingerprint sensor.
- Inspect for Damage: While you have the device open, carefully inspect the fingerprint sensor and its associated parts for any signs of physical damage. If there is damage, you may need to replace the sensor.
- Professional Help: If you're unable to find any issue with the connections or any visible damage, consider seeking professional help. There might be an internal issue that's not immediately visible or a problem related to the battery replacement that requires professional attention.
Remember that working on your device can void the warranty and potentially cause further damage if not done correctly, so proceed with caution.