Sorry to hear about your problem. This is certainly ISP/router related and I’ve asked if one of our Network Engineers could check this out next week, in hopes that they can advise on how to proceed.
With the Christmas break upcoming it may not be possible for them to look in to this until the new year, but I hope to catch somebody on Monday.
You are behind a CGNAT. Ask your ISP if they can get you a proper IPv4 (i.e. one not behind a CGNAT).
Ping me if you need help formulating your request.
Interesting. Did you change router when you switched ISP as well? Do you know if your current router supports UPnP?
(You described a common CGNAT problem, so I just assumed it was. Cudos to your ISP though.)
If you are unsure about UPnP, use miniupnp to test it. Latest version http://miniupnp.free.fr/files/download.php?file=upnpc-exe-win32-20150918.zip
Please pardon my last message in which I said this was ISP/router related - it’s not - it’s an issue on our part and will be addressed with the next patch. Apologies for the inconvenience.
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