I have a problem with the portal in the H.E.L.M. from a Season of the Witch, which won't open for me. I've done the intro mission (the Way of the Witch, I think It was called). Then I ran Savathûn's Spire once, which told me to go to the H.E.L.M but the portal was closed once I got there. I own the season and have finished the Witch Queen campaign. I've linked a video for more context.