Your frog's in the video for less than one second, which makes it impossible to see the problem.

Is the skin peeling off in pieces instead of being shed by the frog in the normal manner? Also, does the frog's skin feel very rough when you touch it? If the answer is yes to both of these questions the nearest thing you'll find to a description of these symptoms (on the Internet) is Nematodes (parasites). The recommended treatments are Ivermectin and Fenbendazole. However, the former will treat the symptoms but the likelihood of the problem returning is great. The latter is a pesticide. The administering of both treatments will subject the frogs to trauma so, personally, I would not use either.

In my experience it's possible to bring the problem under control within a day or two but I never figured out a way to eradicate it completely. I moved my frogs into a bucket with nothing in it but fresh (dechlorinated) water of the same temperature as the tank they were moved from. I changed 100% of the water in the bucket every 24 hours for however long was necessary and removed all traces of "dead" skin. This always worked for me if the problem was caught in time.

If your answer was "no" to two questions above I'm afraid I have no idea what the problem might be.

I doubt that the colour change is anything to be concerned about. There's more info here: https://asknature.org/strategy/pigme.../#.W1NqyrgnZ1s