Safari 17.4.1 can't find government site server

This is the site: https://mybenefits.mcss.gov.on.ca/ sorry didn't know if it would be kept out of the post. When I go to it on this Mac that is up to date on Sonoma says "safari can't find the server". Same thing happens on my other user on this Mac which is using a different Apple ID. Glad it works on that MacBook Air on Big Sur though or I would be locked out of communication with my case worker.

Not using a VPN or apple's version of it. Nothing really changed on my Mac. I thought the site was down originally but then thought to try my older Mac and it works fine in safari on that one with big sur.

Works like that on my other Mac running Big Sur also where everything works. Just can't figure out why it started looking this way a week ago. I always clear everything history and cache but doesn't help. Its kind of complicated since first I have to sign into this other site a govt one like a portal and then click on a link on that site that opens up the one I liked to here. I can see the address bar trying one address during that link process but seems like it fails. So something here doesn't like the handoff between one site and the other it seems.

I installed the safari technical preview also, not sure if it's ok to say that here. Wasn't a beta. But same thing in that app. Didn't work any better. I will try safe mode later just the other user on here is running media on an Apple TV for family so can't shut down or restart right now.

I removed all I could find of the VPN app then restarted and now I can log into that site and it loads fine. Not sure why the VPN suddenly was causing that site not to load. Thank you for suggesting this. It fixed the problem for me. Not sure if it will come back when I re-install the VPN. I did change one other setting in preferences and network but just about hiding my IP. Turned that off but I will install the VPN again and see if that site won't load again. Thanks

I installed the VPN again from scratch and then tried to get to the site and it still loads ok now even with it installed but not using it at the time I am logging into that site. Never used it while trying to log into any site. Still trying to understand why that was causing my trouble loading a site. Never realized it could cause that sort of trouble even when not running the app. Thanks again

I tried to log into that site again today but got the same can't find server again. So I deleted all the VPN files and restarted like last time, but this time it didn't work or fix the site loading. I give up now. So hard to figure this out. I will either use my older Mac on big Sur to log into this site or do a fresh install on my Mac and see if that helps since I never had trouble with this site until the past month. I won't install the VPN on my main Mac also again. Thank you for your help though. So many bugs in macOS lately, not sure if it's something else causing this. This has been my most frustrating version of macOS in decades.

I still keep trying to figure this out but since macOS 14.5 came out today I wanted to see if that fixed this but it didn't. So I wanted to do a fresh install of 14.5 so I could install one thing and setting at a time and see what helps. This government site I use that I'm having trouble with works in a not so usual way. First you sign into one site, then it has a link on that site that will take you to another government site where you are logged in. So it's logging you in from another site.

One setting in safari that broke this once again but then fixed it was under the Advanced tab of settings. Then under Privacy and a check box for "Use advanced tracking and fingerprinting protection". When I turn that on I get that 'can't find server' message when I go from the first site to the second. When I turn that off the second site loads as expected.

So I guess this setting was blocking that link info between one site and the other. I hope this is the end of it. I would like to keep a lot of these settings on but this site I need to go to relies on links to log into other departments of government. So how it is designed is more what I find is at fault here. I wish I could log into the site I need directly but they removed that a few years ago and force you to log in from this main portal sort of site now. Thank you to everyone who helped and replied.