Foreign Object in Nestle Nesquik Strawberry Squares

I purchased the Nestle Nesquik Strawberry Squares product yesterday evening from Niv Gross Market in Derince, Kocaeli. When we opened and consumed it today, we discovered a foreign object inside and noticed a very bad smell. We had already eaten part of the product before realizing the foreign substance was there, and I am especially worried since my young child also consumed it. The product’s expiration date is 12/23/2025, and I still have the receipt (₺104.95 TL). I am requesting a detailed explanation from Nestle about what the foreign object is and a full refund. I expect this matter, which has put our health at risk, to be clarified and handled with the necessary care.