Restart Legion artifact questline

Hello, i’m feral druid who started playing in bfa, at some point i went to dalaran and probably took the artifact weapon questline (i can’t remember) since i have the option to transmog the artifact although i don’t have it. Now, i don’t know how to restart the questline, also when i use dreamwalk to go into my order hall i walk through the portal but it doesn’t take me anywhere. Appreciate any help.