I ordered and installed a "drive coupling" from you and put all back together. However, when installing I had to clamp the motor shaft in order to get existing reverse thread coupling off and in doing so a magnetic plastic cap at end of motor shaft came off. Your parts dept. could not tell me what part this was so I could order it. When starting my blender, it will run 5 seconds, then stop and all red lights begin blinking at each speed setting. What do I need to do to get the blender to stay on and function properly? Thank you.