My PS5 doesn’t seem to connect to the internet anymore and I feel like I’ve already tried basically everything I can but nothing ever seems to work

So basically the last few days my PS5 has struggled to connect to the internet and I don't really understand what's going on. It used to work perfectly fine but ever since my parents got a new modem for the house my PS5 has barely been able to connect to it and for the most part all I keep getting is CE-109503-8 and it says it can't obtain IP address within the time limit everytime I try to connect.

I've tried everything from disconnecting and reconnecting the modem to reset it, turning off and on my PS5 and even leaving it off for a few minutes with and without the power cable connected, resetting the PS5, swapping around the HDMI cable, testing the connection on the PS5, changing the wifi frequency bands in the settings from automatic to 5 GHz and 2.4 GHz, using 8.8.8.8 and 8.8.4.4 as primary and secondary DNS servers and 1.1.1.1 and 1.0.0.1 as my primary and secondary DNS servers, and setting the MTU setting to 1473.

Usually my PS5 is also upstairs in my room which is about as far away from the modem in the house as you can get and I've tried moving my PS5 downstairs in the living room closer to where the modem is but sometimes even down there it struggles to connect but it usually does after a few tries or even immediately but then when I try to connect in my room it just doesn't anymore. Permanently moving my PS5 closer to the modem isn't really an option for me though since I need to keep it in my room with the rest of my setup for personal privacy reasons from my parents and for other things that I do like connecting it to my PC for streaming or recording but there's also no way that I can stretch a whole cable across the house to have a wired connection and with the way the modem is connected to our internet I can't physically disconnect the modem and move it closer or up into my room either so moving things closer straight up isn't an option even though it feels like it would be the only thing that would actually solve these issues. I mostly just don't understand why I'm suddenly having all these issues now when this never used to happen.