Washer is dead. Door is Locked. When I push Control On lights just flash. Replaced interface board 2 years ago.
These machines are good washers, but they are a real problem when this happens.
To open the door, with the power off take off the front access panel and reach up on the door lock side until you find a small tab. Gently pull it down and you will then be able to open the door.
You are going to have to do some continuity testing after you get the door open. Here is the service manual which will tell you how.
I will be working later this week on a Duet Sport with almost the exact problem. I suspect I will be replacing the door switch/lock mechanism, but want to do as many tests as I can before I do so, since it is an expensive part. If I am able to diagnosis the problem on the machine I am working on I will post the info for you.
If you do not find anything I would suggest replacing the door switch/lock assembly, but cannot guarantee this will fix it as there could be problems in the wiring, interace or control board.
Good luck, and let us know what your testing finds out.