I carefully looked first to make sure this topic was already here but did not see it (at least not for the most recent companion app patch, the same day as Wow 9.2.) I can’t see where it says the version on the Companion App.
Some missions are finished, both in BFA and Legion mission board (maybe Draenor too), but I can’t complete them in the Companion App on my phone since the update I had to apply while also downloading the Wow 9.2 patch (for Wow itself.)
So this would be the latest Companion App update, not being able to finish some missions.
I’ve had it happen on a couple characters with no particular rhyme or reason, at least not that I can see.
So I still had to actually get in Wow, hoof it to that era mission board, then have that character manually end the mission. Then I could log out of Wow and continue with new missions on the companion app.