Why doesn't PLA stick to heated bed?
I think you may have used the wrong substance to clean your bed. Try using Isopropyl Alcohol (IPA). You may have left some residue behind from the soap, which is now interfering with adhesion. When that is done, ensure you've gone through the steps for bed leveling again. It's amazing how much of a difference proper bed leveling makes in adhesion. If it still doesn't work, post some pictures up of your results, which will help tremendously in getting you a better answer.