How do you get to motor?

you will to take motor to motor shop, disassemble motor and take bearing shop, OR buy a new motor for less money
copy and paste link

https://evacuumstore.com/p-9980-sanitaire-commercial-upright-sc679-j-motor-assembly.aspx

It sounds like the small silver piece that fell out of your BISSELL Powerforce Helix may be the motor brush. The motor brush is a small, spring-loaded carbon block that makes contact with the motor to conduct electricity. If the motor brush falls out or is not installed correctly, it can cause the motor to make a loud, high-pitched noise.
To fix the problem, you should locate the motor brush and try to reinstall it. The motor brush is typically located near the motor on one or both sides of the vacuum. You may need to consult the user manual or contact BISSELL customer service for specific instructions on how to access and install the motor brush.
If the motor brush is damaged or missing, you may need to purchase a replacement motor brush from BISSELL or a vacuum repair shop. Once you have replaced the motor brush, the high-pitched noise should go away and the vacuum should operate normally.

No reset
you will need to replace the motor

Your new motor should be very similar to the old motor. Compare the two motors to see if you can determine where each wire on the old motor should go on the new motor. If you are not sure it may save you money to have it wired by a qualified repair person. If you hook it up wrong it may damage the new motor and/or other electric components of your vacuum.

i have the same problem and none of these solutions help. they are all for if suction works but brush doesn't. that isn't what she is saying. brush motor works fine. It's the Suction motor that never kicks on. Mine is doing it now and I would love a fix for it. Resetting suction motor. Not brush....

You will need a new motor, not brushes, as the worn motor will tear through new brushes. Search online for the M&S motor replacement and you will see helpful sites that will provide the replacement motor. Replacing the motor is not difficult. Consider replacing both motors as the second motor will go out in the near future.

You are correct, the motor is done. Look at your local vac store for a quality vacuum made by Sebo or Miele. Replacing motors in chinese made vacs is a waste of money as the whole product was made to last only a couple of years

It is quite easy to check this out only if you can just have a multimeter with you.,
Take the panel of the vacuum removed too access the switch and the motor. use the meter to test for continuity of the wire to the switch and then to the motor if there is switching action on the main switch, the the power must come to the motor. however if the motor is not showing a reading , check if it is the brush type motor, if so clean the brush and commutator .or else the motor may need a replacement.

yes but make sure the motors are exactly the same.check the voltage on both of them and see if they are both ac motors and not dc motors.if the new motor is dc it won't work.i have a hoover savvy that has a dc motor that i want to replace with a ac motor

If you are finding BB's. then the bearings are bad. You could pull the motor and take it to a place that rebuilds motors to see about replacing the bearings. If it is a Lamb or amtec motor, there is a number stamped on it, you can match up another motor with that number. Go to a place that sells Vacuum repair parts and they maybe able to get you a new motor.