I was for days without internet and spent more than an hour on the phone with Dell Support to try and solve this mysterious problem. I could find my home network on all devices except on my Dell XPS 13 9360.
After this said call with Dell's support, I tried to recall what changed and triggered this network not to be visible on my device. I had a couple of technicians from my ISP change the router location and they usually have to reset the SSID. They did change it from PLDTHOMEFIBR_NATVILUX to PLDTHOMEFIBR_PLDTHOMENATVILUX.
As I was already desperate for a solution - to be fair to Dell, their Support did arrange for someone to come and visit me - I couldn't not wait anymore and decided to try and rename the SSID myself to see if it solved the problem and the network would become visible again on my laptop. I renamed it back to PLDTHOMEFIBR_NATVILUX and to my surprise and joy, the network was now visible again on my Dell 9360.
I guess the network card does not support SSID that are 29 (!) characters long. It is rather strange because all my other devices were able to find the network and connect to it.
I thought of sharing this on the forum because I did not find anything on this problem online. I did ask the Support staff on the phone if maybe the length of the SSID was a limitation but he did not know what to answer to that.
Lesson learned and I hope this is useful to anyone that finds the same problem.
I'm having probs with an XPS-12 that arbitrarily refuses to see my home SSID despite having like 10 other devices connected to it.
It sees the neighborhood SSIDs, so it's very odd. Changing anything on the wifi causes the SSID to re-appear, so it might be that renaming it coincidentally causes it to appear again (the length isn't that important?)
The behavior is very non-deterministic, so I'm not sure what's going on. It will work for two days, then refuse to see the SSID until I reboot the router and/or change the channel for the SSID, etc.