Sudden and unpredictable loss of IPv4 connectivity

[Aurel81]

Hello, i posted the same problem on the international forum, but maybe ... bigger hive, bigger hivemind ;-)

i am fighting this problem since i started using my FB in bridge mode (germany, Vodafone, Cable, DualStack)
this problem occurs suddenly and unpredictably.
Last 3 days i had no issues (havent even opened the Opnsense UI the last 24 hours), everything worked finde (including admistration via wireguard from outside) but today, something striked back.

Affected is every device, no matter if its a physical computer (os independend), a VM/LXC/IOT ... even Opnsense itself (which gets the WAN directly over PCI passthrough)
DNSlookup works fine.
Ping, traceroot, opening internetpages or connecting to services on IPv4 dont work, IPv6 work perfectly.

i am owning a FritzBox 6660 and tested with an 6690 as well. Same issues on bridgemode.
FB in regular Routermode had no problems (never had before, or happened while i tested it the last weeks)...

any idea ?

imho it is a problem in front of opnsense ... either FB (it occurs on non bridge as well) or its an ISP problem, as sometimes reconnecting solves the issue temporarly...

any ideas ? i am willing to provide any screenshot that might help you , figuring out the cause of the problem.

thxia