Check the draining system from the base of the tub going to the drain pump then the inside the pump and disconnect and clean the hose leaving the pump and the back of the unit may have a hose that connects to the rear of the unit that things get clogged in that as well........Basically disconnect and inspect all drain system hoses and clean out with a hose take a shopvac and clean those hoses........If all checks out and no major clogs are found take a multimeter and voltage test the drain pump during drain/spin cycles numerous times...........If you get 120v every time for at least 10 times testing it's your pump going out..........if you don't get 120v every time you have it in a drain cycle it's probably a main board or wiring issue.