Does anyone know what this is?

I had a fungus problem with my axie a few months back, but she's been fine for a while now.. I finally got her tank cycled and I have a master water testing kit that I use to do weekly water tests as well as 25-50% water changes weekly to keep the tank free of nitrate build up. When she had the fungal problem I took her to the vet and they cut a skin sample off her tail for testing, since there were some little spots of fungus on that area. I noticed after a while after the visit to the vet that the skin around her tail slowly started to look like it was dying.. It's become transparent and floppy like dead skin tissue.. I was thinking it would maybe fall off but it looks like surface area of dead skin is increasing. There is no fungus growing on it so I don't think it's infected and she hasn't shown any signs of stress. Could something have happened when the vet took the skin sample? I've heard of fin rot in axolotls… Any advice would be appreciated!

Its ok . The tips of axolotl tails get knocked about a fair bit so its just where it is growing/ repairing.

Thanks for the reply I was worried the vet might have accidentally hurt her, but I'm glad to know it's nothing to be concerned about!