How to cure this unpleasant Schnoodle habit?

Our 5 1/2 month old schnoodle has been housebroken for many weeks. My husband was inattentive one day and the puppy pooped in our bedroom.
Since then he had been refusing to poop at night outside but waits until he's inside and poops in same place 3 times now in our bedroom. We always clean with Natures Miracle thoroughly.
We keep the bedroom door closed since he has lost the privilege of going in there except for sleep at night so its not happened for days.
Tonight he asked to go in there to see if I was sleeping in there my husband thought (I am out of town this weekend). Husband and puppy went in to bedroom and before husband realized it, puppy was pooping. He shouted at him and took him outside. What is the remedy for us please?
It's becoming a habit I fear.