GE Washer Not Agitating

The washer does everything but agitate. Is it a coupler or a transmission problem? I can’t figure out how to remove the agitator. Please help!
Thanks

To remove the agitator, place a strap under it near the center and yank upwards to pop it off. If you can rotate the agitator coupler easily by hand, the splines are probably stripped out. Remove the bolt and coupler to inspect inside it for stripped splines.

Eric