The story is that at the beginning I had IPv6, and a shared dynamic IPv4 behind a CGNAT, I asked for a rollback to a full duplex static IPv4 and for three years I had both a static personal IPv4 and an IPv6. A few weeks ago my router went down and since it went back up, I no longer have an IPv6 address. I called my ISP and they explained that I could either have IPv6 or a static IPv4, but not both, and that it's abnormal that I had both for so long… welp, it's sad to see IPv6 but getting it back is not worth abandoning my static IPv4 and going back to a dynamic shared IPv4.