Many Xperia 1 and Xperia 5 users reporting finger print sensor issue on SONY's official forum.

Xperia 1 issue

Xperia 5 isssue

In most cases, the sensor fail to recognize fingerprint but there are many users reporting the sensor completely fail to work.

SONY has not respond to the report at all although the thread about this issue is the longest in Xperia 1 forum. 

SONY should:

1.  acknowledge the issue
2.  explain the issue (cause and solution)
3. announce recall for repair if it's due to hardware defect.