A song called "Don't stop knocking on my door" or "Knocking on my door"?

Question

I am trying to find a song that is called either "Don't Stop Knocking on My Door" or "Knocking On My Door". Something to that extent. It's an upbeat song, and was featured on this season of "So You Think You Can Dance". I'm 98% sure a woman sings it. Please help, thanks.

Answer 1

Was it the dance where it was Twitch and Katie? If it was then it's probably the one by Duffy.  

Answer 2

I know two songs:

"Knocking on Heaven's Door" by Bob Dylan,

and,

"Don't Go Knockin' on My Door" by Britney Spears.