Unable to access HA locally with a new router. Partial access through Duckdns

Hi everyone,

I have bought a new router, Archer AX73. Migrated form Netgear R6300 (started failing). My HA is running on Virtualization station on QNAP NAS. Fixed IP assigned through CLI. On the new router I can see that the IP is assigned correctly.

I am unable to connect locally through http://IP:8123 (ERR_CONNECTION_TIMED_OUT). However I am able to access partially through web using duck dns, however HA does not work properly, can see dashboard but MQTT devices are unavailable, cannot access NodeRED, probably because HA ip cannot be accessed locally. I can control some devices that do not rely on mqtt servers (xiaomi yeelights).

I assume that there is some router configuration I need to change. Switching back to old router, everything works fine.

SSH port 22 works
HA console works
Ping HA IP request time out
ipv4.dns set to router ip
ipv4.gateway set to router ip
Fresh install OK, accessible from local, but after backup restore connection refuse, no longer accessible from web through duckdns

Any pointers how to solve this greatly appreciated.