[Xperia Z] wifi problem unstable

[M4r3ch4L]

Hi

Since a few weekes, when my phone is connected to my wifi (it might remain everytime connected to it) it doesn't allow my phone to load webpage

For example:

I go on google, I type a search, then I hit some website to visit but I get the error "err_name_not_resolved"

I switch off then on the wifi on my Xperia, then it works again for a few minutes, then the problem mostly come back... Sometimes it work fine...

I checked everything...

there is no power saving on the wifi

my router is ok

the wifi settings are ok

Sometimes the wifi icon pn the xperia disappears with no reason and then come back even if I didn't asked for it

and most of the time the icon stay lit but I can't load anything such as webpage or apps

I don't know what is happenning...

I checked this already with no help:

/t5/FAQ/Wi-Fi-problems/m-p/348104#U348104

[Phy]

Does it work on safe mode?

How to boot on safe mode
http://talk.sonymobile.com/t5/FAQ/How-to-boot-your-phone-into-safe-mode/m-p/348008#U348008

How to boot on safe mode on Lolipop
1. press and hold the power key
2. once you get the pop up menu 
3. press and hold "power off" 
4. Boot on safe mode should become available

[M4r3ch4L]

Hi
I'm going to try this during the next week and see if it solves this issue because i'm still getting it