[Q] Sony M4 16 GB random reboots - Sony Xperia M4 Aqua

Hello, i just bought this phone from the shop that begins with "a" and ends with "zon" - france, because it seems that only on the france shop it's possible to get the 16gb version...
Well, the problem is the phone keeps randomly rebooting itself!
While playing, while logging into skype and also just while working with some various applications.
What i can only say is that the phone till now was not used still with any sim because i have to take time convert my microSIM into a nanoSIM, it could be that the apps go mad and the system reboots for this?
I tried many factory resets.. any suggestion to get a log and understand?
Here some data:
Model Number: E2333
Processor Info: Qualcomm Technologies, Inc MSM8939
Android Version: 5.0
Baseband Version 1.0.J.0.0_8916_M:2008606.50.00.504171_A:200806.50.00.<build_no>
Kernel version: [email protected] #1 Sat Apr 18 05:41:22 CST 2015
Build Number: 26.1.B.1.85
In the About Phone -> Diagnostics i can see the following
Xperia M4 Aqua Dual (E2333)
IMEI: ....
Capacity: 11.07 GB
System Incidents: 17 in last 10 days
Sub system incident: 0
Android Version: 5.0
Customization: 1293-7732 R6A
Current Software: 26.1.B.1.85
Software up-to-date: 26.1.B.1.85
I also took a screenshot here:
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
There's a way to read some logs and understand why of this crash?
If i click over the System Incidents option it only gives me
the date and time but not the reasons or some more verbose details :\
I wonder