i GOT THIS RIGHT OFF THE COCA-COLA WEBSITE:
We know you must be very disappointed with the situation. As with other beverages and food products, some ingredients have the potential to stain certain types of materials and fabrics.For this reason, we cannot guarantee or be responsible for the result of any stain removal method; however, you are welcome to try the following:
Take a spoonful of mild detergent and add it to a pint of water
Shake the contents until dissolved
Dip a white cloth into the solution, just dampening the cloth
Gently rub the cloth on the spot in a circular motion, not changing the direction of the motion
Repeat process
After most of the stain is lifted, cover spot with a clean, dry, white cloth
Place a heavy object on top of the cloth and leave overnight.
If this does not remove the stain completely, we would suggest contacting a professional cleaning company or the manufacturer of the stained item. They may have other suggestions or be able to professionally remove it for you.