That was his idea, to find out which operating system (also in relation of Android version) you are using.
So as it seems it’s Android 7. It actually (still) has issues with reconnecting to known wifi networks. This is one among other bugs which still has to be fixed.
In this forum we have a topic about the most annoying bugs, yours should also be covered here.
More about the remaining bugs is available on the bug tracker.
Btw. Fairphone itself not only ships/maintains the known Android xx operating system but also a “Google” less OS offering root rights called Fairphone Open OS (FPOOS) while the classical Android is abbreviated here as FPOS.