Blue boots take the remaining bags back( along with your receipt) and if you have any of the open bag left take that as well to show them what they contain.Be polite and explain that the contents are not as described and not fit for the purpose they are being sold for. You hopefully will get a refund. I purchased 3 bags of Growise from a local independant garden centre ( I live in mid Wales) and it is very good . I shall be going back for more if they have any left.
I purchase some bags of arthur bowes, I had some last year, which were very good, but this they were dreadful looked like pine needles and the bags were alot smaller 35 litres compared with 50.