"Key's In The Mailbox" by Barbara Mandrell, from her 1991 album of the same name. The song is a cover of a 1960 Freddie Hart tune which peaked at #18 on the Billboard Country Singles chart. I always thought this was one of her best recordings from the era after the genre's seismic shift in sound with the neo-traditional movement in the late 80s. Mandrell changed her sound in an attempt to adapt, but country music had already mostly left behind the 'old school' artists of the 70s and 80s by that point. Much of her catalog was lack-luster after around 1986, but she still managed to produce a few diamonds in the rough, such as this.