would

didn't は　電話をとらなかった　　という過去の事実　を示しています。

wouldn't は　電話をとろうとしなかった　という　彼女の　意思　や　彼女の態度を　表しています。

I've searched the difference between wouldn't and didn't on the web. I found a site about 'didn't', but couldn't find about 'wouldn't'.
so this is my unfounded conjecture. (https://ejje.weblio.jp/sentence/content/conjecture).
I suppose the phrase 'didn't' means denying of phenomena (action,fact,event,etc.）of the past and the phrase 'wouldn't' not having had the will for phenomena (action,fact,event,etc).
in short the difference'd depend on having the will or not.
:didn't.
https://www.manythings.org/audio/sentences/2162.html