When we upgraded our TV Box, Virgin included a slightly upgraded router and I therefore installed it. But it would not remember when I changed the login password or anything else. I repeatedly had to reset it to get back in only for the same things to happen. I rang their tech line and the Indian grunt had no idea why I should want to or what to do about it. I was fortunately escalated up the chain to a most helpful and very knowledgeable English guy who sensibly suggested I simply reinstall the old one and facilitated that.
My experience with the grunt though strongly backs this up. I expect I was the only person he had ever dealt with who did anything of the sort. Our router is renamed, has a custom pword, does not broadcast (you have to know it's there AND the correct name) AND there is MAC address filtering so your device needs added unless I tell you the name of the Guest mode and pword (of course it has a pword).
I'm not even a techie, I'm a bioscientist. I've just informed myself over time. At one time I ran Mac support for our large lab because IT didn't have a Mac specialist. Instead of waiting for them when new kit arrived I would note the MAC, inform them and it was on the network by the time I got it fully out of the box.
My wife does have a CompSci degree but I still run IT support in the home, including on her Windoze laptops. Turning the wifi on and off is a difficult thing apparently. Though to be fair it's harder than on the Mac (click symbol on menu bar, choose turn off, turn back on).