Review on Phenolphthalein Indicator Solution Dropper Containing by Christopher Bates

So I ordered for high school science lab. Have been doing this lab for years. I did a diluted vinegar test which usually works but to no avail. I tried 100% vinegar, the color did not change. It was two bottles so I tried another bottle of straight vinegar. I even tried lemon juice and muriatic acid but nothing. Nothing at all.