I have Home Assistant on two physicall locations, both running in docker on Pi4. Both locations have an edgerouter setup by me.
I haven't made any changes. This has worked excellent for a long time.
I have two devices, a Sony phone and a Samsung tablet. This past thursday something changed, connecting to location 1 through mobile network all custom slider-cards show configuration error. On wifi it works. But on wifi I can't connect to location 2, neither from my phone or tablet. Sharing wifi through the phone to the tablet works and connects fine.
I have checked and reset connection settings and home network. I have updated let's encrypt certificates even they were far from epired, checked updates...
What might be the cause of this? I haven't change anything.
im not an expert but this sounds like something is cached and bottom line unavailable.
Do you have ipv4 on mobile or ipv6? Is both forwarded on your edge router?
Can you connect/use something like VPN and/or zerotier one? because those will give you ipv4 adresses and you can maybe pinpoint what the issue is.
On some Carriers you can explicitly Change APN to explicitly force ipv4.
For example Telekom Germany:
Thank you for your suggestion. According to test-ipv6.com my phone (on mobile data), location 1 and 2 are all ipv4.
I use Dynudns and of what I can understand they are full support of ipv4.
I can still connect to loc. 2 using a couple of other services hosted on the same pi.
The companion app was updated june 11:th, a full week before my problem appeared.