The callout scores are pretty good. The most important score is "Net Positive" (percentage of people who gave it a positive rating subtracted by the percentage of people who gave it a negative rating). In terms of Net Positive, it's ranked #11, which is good.
So with that being said, I have absolutely no idea why it's stalling on pop radio. It has good callout scores and very good sales for a song that's only in the 20s on pop radio. It should be doing much better than this
The only thing I can think of is that A LOT of new songs by big artists are coming (Taylor, Justin, Macklemore and Nick Jonas), so this might be getting a bit overshadowed.