Poor product/application

The wall covering bubbled. To add insult to injury the product is expensive and I paid for them to professionally install. I was told after the fact this must be due to the paint that I had used on the wall (the wall was painted with a plascon brand one year prior). They left it at that. They said "sorry" and "I wish there was more we could do". Still insisted that the full amount be paid. Unacceptable.