No NAT Found reported by lotus

I have problem when running lotus daemon (and lotus-miner). It reports:

basichost basic/natmgr.go:91 DiscoverNAT error:no NAT found

My PC is behing NAT, but I have NAT working (Mikrotik), I am also able to telnet from the internet directly to the open port on my PC. But the lotus still claims, that NAT is not working.
Is there something I am doing wrong? I use Ubuntu 20.04.1 with latest lotus version (1.1.2+git.d525acded).

I found a possible solution there (set DNS to some public server), but it didn’t help.

Thank you,

its not a problem… after few min it must go further