Help! Slimy sweet potatoes!

Rawsiki

I cubed a raw sweet potato and then put it in a zip-lock bag and stored it in the fridge. It’s been in there for maybe 3-4 days. I opened it today to eat and I touched them, and they are all wet and soft and slimy! I’m scared to taste it! Nothing spilled on them or anything, and there’s no hole in the bag. Where’d I go wrong?