Just moved to ubuntu on my macbook and spend whole day trying to open transmission port 51413.

Already done:

1. I have ufw but i opened ports there and tried without it - probably not the problem

   51413/tcp                  ALLOW       Anywhere
   51413/tcp                  ALLOW       Anywhere (v6)
   
   21/tcp                     ALLOW OUT   Anywhere
   80                         ALLOW OUT   Anywhere
   143                        ALLOW OUT   Anywhere
   2049                       ALLOW OUT   Anywhere
   110                        ALLOW OUT   Anywhere
   135,139,445/tcp            ALLOW OUT   Anywhere
   137,138/udp                ALLOW OUT   Anywhere
   25/tcp                     ALLOW OUT   Anywhere
   631                        ALLOW OUT   Anywhere
   443/tcp                    ALLOW OUT   Anywhere
   53/udp                     ALLOW OUT   Anywhere
   123/udp                    ALLOW OUT   Anywhere
   993/tcp                    ALLOW OUT   Anywhere
   465/tcp                    ALLOW OUT   Anywhere
   51413/tcp                  ALLOW OUT   Anywhere
   

2. router Pirelli DRG A125G; tried disabling firewall, forwarding ports according portforward.com but I have no experience with such thing so I dont know if i succeeded On transmission still shows port blocked and nothing is downloading...

3. CanYouSeeMe.org tried tu use to see if ports are open but it shows that port is blocked

4. Also tried qbitorrent it also doesnt work