Black slime, type fungus in C***** UHT Long life milk

I bought a box of 6, Long Life Full Cream UHT Milk, which is a C***** Brand. However the first one that I opened was sour. I threw that one away, and opened the second one, which was starting to go sour as well. I then opened the 3rd one, and also sour. The expiry date says 21 May 2021. However my husband decided to rather empty the carton of long life milk and throw the empty carton away. I am completely disgusted with what came out. There appears to be black slime, some sort of fungus that came out. I will never in my life buy C***** again. I have the photos to show C***** what is in their products.