I'm playing Sebille main with Lohse companion (lone wolf). At some point around the time I performed the Ascendancy ritual (and certainly afterwards), Sebille became stuck out of combat. I cannot force her to take damage, or enter combat with her.

It resembles what I'm reading about the early-access companion bug where you could wind up with companions stuck in this state due to status flags not resetting.

I'm pretty sure this save is bricked. It's a disappointment, but I do love this game, so I'll keep on trucking with a new save file.

having the same issue.

Yeah happened to me with Fane aswell

Same issue made the following post "Companion unresponsive and in godmode" do you get the same problem? You do the stealing thing like I wrote in EDIT1 as well?

EDIT1:
Someone found the reason for this Bug:

"Possible NPC bug that disables the ability to talk"
You talked to Nicolas in Driftwood

Confirming that I was also stealing using her, yes. And yes, I spoke with Nicolas in Driftwood.

Same issue - hopefully Larian will patch in a fix for this - or somehow allowing your character to be killed so they can be resurrected again will reset this.