No, it is not necessary to stop taking it if it is just collagen without other ingredients.

We consider collagen in its pure form a food, not a supplement, as collagen is nothing more than hydrolyzed gelatin, meaning it's broken down into smaller molecules.

Throughout evolution, our ancestors also consumed the parts of the animal rich in collagen, which contains 25% of glycine. Today, we consume only muscle, which contains only a minimal amount of collagen. Thus, for 2.5 million years and up until a few decades ago (even our grandparents ate foods rich in collagen), the body obtained glycine through the diet.