Grab the locking piece with a pair of needle nose pliers close to the back of the bolt head and pull the LP rearward. Once the locking piece is far enough back inside the carrier, rotate the bolt head and it should solve the puzzle. You may need an extra set of hands.
It's been a while since I've been in the same predicament but from what I recall this is how I did it.
What happened was the LP was rotated a extra 1/2 turn past where it should of been. When the bolt head was installed and twisted the LP unlocked from the carrier and is forced into the bolt head pushing the rollers out. Now the bolt is aligned wrong and everything is stuck. Depressing the LP back into the bolt carrier and rotating should allow the bolt head to be removed.
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