"developer options not available for this user" Marshmallow
<p>I'm experiencing very interesting problem with my Galaxy S6 Edge phone with marshmallow. When I go to developer options. Instead of a long list of options I get a message of "developer options not available for this user". As far as I know, I don't have any other user (I even don't know how to add a user, to be honest). I saw a couple of people had a similar issue with kitkat but they weren't even able to get the developer options menu item in the settings. I have that developer options item and I actually have it for a while. I haven't done anything special recently and I wonder anyone experienced this before and whether there is a way of fixing this without factory reset.</p>

<p>Finally there are a couple of more symptoms which may/may not be related with this.
Task Switch button at the bottom of screen doesn't work.
The settings button on the notifications panel doesn't work</p>

<p>EDIT : I had to fix the issue by factory reset, I didn't have the chance to try Victor's answer but I am accepting it as the right answer since there are some people who were able to fix their issue </p>