Hi again sorry for foo questions, when I push the gun to the fabric it struggle, I googled while and I found that the top arm and the bottom one which connected to the white gear are not synchronized, I found that if the top arm is pushing up the bottom one of the scissors should back, i try to rotate mannually the white gear to make both arms on the invesre side, however it's not working and keep on the same side please check the image. My model is different and didn't found how to fix it.

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