Make sure repeat is deactivated:
From the now playing screen, bring up the scrubber bar(tap the screen): A small icon that looks like two circular arrows is on the left side below the scrubbing bar. Tap this icon once to repeat the album/song. The icon will turn blue when repeat is activated. Tap the icon again to repeat the current song. The icon will change to show the number 1 inside a blue circle. Touch the icon a third time to cancel any repeat. The icon will turn white when it's deactivated.