The extruder gear is stripped or the tension is wrong. Clean the gear with a brass brush. Adjust the tension screw on the extruder lever (clockwise for more grip).
The user manual includes a maintenance schedule, and for the X-Pro, you should pay attention to three things: qidi x-pro manual
| Material | Nozzle Temp | Bed Temp | Enclosure Fan | |----------|-------------|----------|----------------| | PLA | 190-210°C | 40-50°C | Open door | | ABS | 230-240°C | 90-100°C | Closed door | | Nylon | 250-260°C | 70-80°C | Closed + desiccant | | TPU | 210-230°C | 40-50°C | Open, slow speed | The extruder gear is stripped or the tension is wrong