I feel the performance slow down while taking photos.
Restarted the phone while the battery level about 60%.
After the xperia logo appears it just shut down itself and restart. It goes on in a loop until low battery.
I found no solution and decided to repair software with pc companion.
Unfortunately all data is lost. 
What could be the reasons for this rebooting issue? Need to avoid it. Very bad.
Hi @Sanya88, welcome to the community. I am sorry to hear about this issue
If you have aleady completed the software repair using Xperia Companion step then I recommend you contact your Local support team to arrange an assessment.
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