How to reset workout goal to "Open"?

My Apple Watch insists on a 4,000 calorie goal for my outdoor walk. How do I change back to "open" goal?

I tried deleting the outdoor walk and then re-adding it, but it still comes back with the calorie goal. I also force rebooted. Again, no effect. I aldd as I tried setting calories to zero. Again, no effect.

This is really annoying. The same question was asked 4 years ago, I see, and no one knew the answer.