The mixing bowl may not be correctly assembled.
Try to remove the plastic base from the mixing bowl, place the knife and assemble it once again.
- Check if the knife is spinning after the assembly.
- Check if the motor axis is turn freely..
- Check if the plastic base fits tightly to the mixing bowl.
- Check whether the mixing bowl base is locked in place correctly.
Objects on the base unit.
Please check if some food or objects have settled on the Thermomix® base unit. Once you identify such objects, please remove them and try to place the mixing bowl once again.