X2 Visa Extension for Tourism?

Hi, I'm studying in China for 30 days, but I wanted to stay here for longer, after my studies end, so I can do some more tourism (my family is visiting after I finish my studies, and they've already booked everything, from hotels to flights, accounting for me). However, my X2 Visa is valid for only 30 days, which means I would need to extend it, somehow, for me to be able to stay and do tourism with my family. I've asked in the Immigration Administration about this and they mentioned the only way I could extend the visa is if my University in China (BIT) could issue a statement saying I would be staying/studying for longer. In the meantime, I've asked them about this and they just said no, without elaborating much further. What can I do in this situation?

In my head, it would make sense to get another tourism (L) visa for the final days, but I'm not sure this is even possible (they mentioned something about it not being possible to have 2 visas simultaneously, but I don't see why that is a problem...)

Anyways, does anyone know what the best course of action is, in these circumstances?

(Extra info: I'm from a country which doesn't have access to the 144h or 15 day visa-free grace period, unfortunately. )