Bad experience in 3l Robertson wine natural sweet

I am very disappointed with Robertson 3lt box Natural sweet. The wine tastes like rotten g****s. I bought the one thinking the celebration of my sister will be much more nicer if we buy Robertson wine,only to find out that it was expired orr rotten. I am very much disappointed since ppl thought I bought cheap wines or may be someone was selling from back door the way the taste was so disgusting.