Fill in the gaps with wouldn't + the verb in brackets.
(open) I was sure I had the right key, but the door .
We use "won't" and its past form "wouldn't" in the meaning of "do not want", "refuse", "be unwilling" to do something.
I'm trying to talk to him, but he won't listen. (= he doesn't want to listen)
I was trying to talk to him, but he wouldn't listen. (= he didn't want to listen)
— Why are you angry? — The car won't start. (= it "refuses" to start)
He was angry because his car wouldn't start. (= it "refused" to start)