I have a galaxy J6 sm-j600fn. For the last month or so, using wifi on it has become pretty much impossible. It's horrendously slow, YouTube is like watching on dial up, constant buffering, downloading files keep failing... I've tried running everything I can find in the device care settings, I've forgotten and reconnected to my wifi networks, done a soft reset, reset my network settings, nothing made a difference.
It is definitely my phone not liking wifi - other devices have no issues with the same networks, and 4g works just fine. When I ran it in safe mode it worked fine, making me think it's an app causing the issue, but I can't tell which one.
Is there any way of drilling down to find the problem app, and anything I can do otherwise short of a factory reset, which would be my last resort?
Wipe cache partition could help ...
You can also check if you can find your answer there:
I know, it's not the same device but problem is the same