hiDude your baseband is from KITKAT. Update it ASAP from here:
Your device is dying with 5 year old baseband that should NEVER be used on marshmallow ROMs. Update both bootloader and baseband! There is a reason we put the "report checklist" in OP.
since one week i'm having the same issue the wifi connection drops everything was working fine before so i thought its the router problem or the sittings about "keep WLAN on during sleep"
so i kept trying bit without luck , as the image i have a new "i think" baseband so any recommendations what to do , i was thinking of dirty flash again