Cannot access 192.168.1.254 to log in to gateway modem

Hi, thank you for your replies/suggestion. Before I continue, let me ask this; should any of these measures be necessary? In the past (as recently as 2 weeks ago) I have accessed the modem configuration successfully dozens of times simply by typing the IP address into the browser. It seems like this issue began after contacting tech support a few days ago, and having them investigate why my TV signal was lost.

I have tried Edge, Chrome, Firefox, and Opera browsers. Yes, I have tried https. I have tried clearing cookies and the cache. I have added the IP address to 'trusted sites' with and without https. I have tried from 3 different computers, 2 connected directly to the modem by ethernet cable, one laptop via WiFi, and my Android phone via WiFi. I have used all of these devices to successfully connect in the past, simply by entering the IP address 192.168.1.254. It truly feels like the issue is with the modem. On 2 occasions, after a very long wait, I have seen a login box, but as text and not as the actual HTML login page. Typing in credentials did nothing, the browser page did not advance and just hung like there was no response at all.