There have been 2 significant changes in my setup recently: I changed ISP and I switched to SurfShark as my VPN.
I changed ISP about a month ago, going to a cellular service (T-Mobile) for the first time; therefore there is no cabling involved so no traditional cable modem and router. I do have a device from T-Mobile that is a cellular transceiver and provides the modem and router functions. Although I can't be certain, this problem began about the time I switched ISP. Coincidence or cause? I don't know.
I changed VPN provider a week or two after changing ISP. Some info I saw online said that a VPN could be causing the problem but only suggested disabling it, which I do NOT want to do. I have found nothing to indicate that SurfShark is the problem, and it is a very widely used platform.
Searching I found an article saying this is only a problem with Firefox. Well, there have been Fx updates lately, too. I went to the Mozilla Support page and found recommendations to choose No Proxy Server in network settings. I tried that; it made no difference.
Has anyone else experienced this issue? If you solved it, could you please tell me how? I'd also like to have a better explanation of what causes it. The error message itself is rather non-specific. I don't know if the connection failed because of security problems or signal problems, for instance.


