The fingerprint stop working, when I try to register a new fingerprint in Fingerprint Manager, it says "fingerprint enrollment time limit reached". Then I try the Xperia Tests > Fingerprint Sensor > "negative result".

I also tried factory reset, it worked for a day, then fingerprint stop working again.

I found a workaround solution though. Goto Apps > Side Sense > Remove cache, then reboot. The fingerprint will work for a day, then stop working again.

Is it likely a software problem?