It's not the string. It's the bow. Is it the MA you list? String bow, rest good end on the floor and sight down the string. Twist should be obvious. Grab the fade area on the twisted limb and the nock end of the twisted limb and twist in the opposite direction. String will move back toward center. Twist past the string groove and hold it for a while -- do this several times until the string wants to stay centered in the groove. When the string wants to stay centered, draw the bow and let it back down and see where the string lays. If or when the string falls back into the groove, try one shot and look at the string again. Repeat the procedure until the string always comes back into the string groove.
A little hot water will warm the offending limb if the above doesn't work. Warm gently the limb and repeat the above process.
If that doesn't work, it will be time to a trip back to the Black Widow hospital in Nixa.