I’m not sure either especially since your loom is newer. I’m assuming the correct texsolv lengths were used for upper and lower. You’ve adjusted the beater. Is the warp over tightened? Could a thread be crossed so it’s preventing a full opening of the shed?
You wound the warp in the back correctly- over the back beam?
I did that once after threading oodles of heddles. Ugh.
I’d contact Louet on their website if all fails. . Dave is helpful and speedy. Let us know what you find.