It sounds like the driveblock needs replaced. The drive block is what holds up the spin basket. If the drive block strips out you will have the symptom you described. I am sending you an image to access the agitator and replace the driveblock. Remember to
to the washer before attempting access.
Please click on the images below.
In the agitator image below screw number 2 is not located at the top & you will need a half inch socket extension to remove the spring retainer number 14. You will also need a spanner wrench to remove the driveblock.