After running with Piper for a while, I left her in Sanctuary. I assigned her to one of the scavanger stations I got there (I got 3).

Then, after a few quests I tok her out for a walk again. After getting her perk, I again left her in Sanctuary to take Dogmeat for a walk. But now I can not assign Piper to anything anymore. She just walks around in the settlement and talks.

This also goes for Dogmeat, Codsworth and Nick so far. In workshop-mode I can no longer command or assign any followers (works fine with settlers though).

Do anyone know a fix for this? Or know if it's supposed to be this way?