Hi,
since a few days I got finally IPv6 enabled on my internet-connection (new router installed). But since then, the Garmin Connect App does not work anymore, when the phone is in the WiFi.
And before you ask: EVERYTHING else is working. Like a lot of other apps no issues, all websites even when performing extensive reachability tests. There is not a single issue. And the issue occures on two different phones, both of which have no other connection issues.
I have a second wifi (VLAN) without IPv6 and there the app is working, so it is 100% a problem with IPv6. There is no firewall active, so that cannot be an issue either. I also use the same nameservers for IPv6 and IPv4 (Quad 9 and the IPv6 version of 1.1.1.2)
What is so specific in the Garmin Connect app that there is no connection possible over a native IPv6 network? Im using a /56 prefix without address translation. Anyone else using IPv6 at home?