It was raining today and while walking up to my car I unlocked it and noticed the passenger blinker wasn't working. On my way to autozone the blinker was doing as it should when a bulb is out and blinking quickly. I replaced the bulb and it still wasn't working. I then decided to swap the drivers bulb and original passenger bulb I thought was out and they both worked. Drove home and it was fine. A few hours later though the passenger blinker is out again. Any ideas why?