Why is the Y-axis power weak for RDC6555G controller?

My device is equipped with the RDC6555G control system. I am preparing to cut the workpiece, but I found that there are significant differences in the cutting effect of the device in different directions. When the shape is cut along the X-axis direction, the laser power performs normally, the material can be smoothly cut through, and the incision is also relatively uniform and flat. However, when the device moves along the Y-axis direction for cutting, the laser effect is significantly weakened, and under the same power parameters, the material may experience continuous or incomplete cutting. I can't understand this phenomenon, who can help me? Thank you.