Hello expert community!

I've recently started playing online with friends on my Nintendo Switch.

However, after playing online once, the network started to struggle. Whenever I want to connect, it tells me that "my network connections are not suitable for playing online". Ironic, given that I can play plenty online on my PS4 and can stream without struggles. Also I need to mention that, sometimes, for whatever magical reason, it does work. I really wish it were a case of not-working versus working, but the middle ground is just confusing (so far I've tried around 20 times and 2 of these it let me through. Like, what???).

I've followed numerous tutorials online (yes, I looked at the Nintendo help site which is not helping at all), and I've, yes, reset my router. 

Part of the problem might also be that I am only having WIFI through the student's home which never really was an issue before. Honestly, I have no idea what to do and quite frankly I have no idea of router's in any way, shape, or form. So following the online tutorials was already difficult and worse to see them not work out.

I cannot port forward because Nintendo wants a range instead of one clear number (which the tplink settings don't allow for if I'm correct), and setting up a DMZ with the address of the Switch entered into the router's settings also did not work.