[Grammar] Why are you wearing coat here?

[atabitaraf]

Why are you wearing coat? It's pretty warm here.
My question is: every singular countable noun needs an article and coat is not an uncountable noun but why the sentence 'Why are you wearing coat here?' is used a lot and sounds natural to me?

 

[Raymott]

It's wrong. That's not a proper English sentence.

 

[atabitaraf]

Thank you, you got me off the hook.

 

[Raymott]

I'm glad that we now have it covered.