GE front load washer will not complete spin cycle

My GE front load washer ‘paused’ with 15 minutes remaining while washing a load of towels. I started the load before leaving the house and this is where it was when I returned. I pushed ‘start’ and it started and then ‘paused’ again. I think maybe the load was unbalanced sometime during the cycle and was unable to balance itself and it created the problem. I removed part of the load and did a ‘drain and spin’ cycle only. It was successful. I put in another load (not towels) and the washer filled and then stopped, but the time continued counting down. I emptied the washer and we ran the test cycles. The only error code was E31 and we checked the drain–nothing was in it. We continued through the tests until we got to t06. The washer filled fine, but would not drain. We concluded the water pump was bad and we replaced it. I started another load and it got to the spin cycle and it will spin for about a minute, stops, adds time, spins again, stops, adds time, etc. until I stop it. It will not go into fast spin mode. We did the test run again and we have no error codes and it successfully completes t06 with the new water pump. Any suggestions on what to do? Thank you.