Halsin will not stop repeating this certain dialogue with Astarion. I had him say it about 6 times when I was exploring one area, to which I then had to just send him back to camp for good because of how annoyed I got lol. I had a similar bug with Minthara and Lae'zel dialogue near Basilisk Gate but not nearly as bad as this one because it's in every area Halsin will repeat this line.

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