Poor app and development team, with no interest from the Company to assist with their problem

For over 5 years I bought a lot of books from Voelgoed winkel, for more than 5 years I have bought these books which have always worked. Now suddenly there is an app that refuses to open the books. Despite numerous requests to Melissa and recommended stupid work around it still refuses to work. She states that the problem lies with my APP which they implemented, how is this my problem. Obviously developer does not know what they are doing and no testing took place. I want a link to the books that I bought so I can open them and read them, I paid for these books, they were not for free. For a Christian Organisation to treat people in this manner is disgusting. Purchased books and answers must be supp**** before end of June