Maytag Washer Not Draining and Displaying Suds and F21 Codes

I had the same problem, My issue was a small sock that was sucked into the drain tube at the bottom of the washer. The technician removed the bottom panal and drained (a lot) of water from the tubing, then the sock came out, it had been preventing the water from draining out. It didn't seem to be a difficult repair to do on your own, Good Luck