Unhappy client

I bought a kreepy krauly bullshark auto pool cleaner from checkers. On arrival at the house and fitting it it did not work as expected. Unfortunately the box got rained on and got destroyed. We have the receipts and never used it. We took it back to the shop and they advised us that the shop will only refund us if we contact kreepy krauly and they sshould sent someone to test it and confirm that it is not working. We did that and someone was assigned to our case by the company. He came and did his assessments. He agreed that their kreepy krauly could not work on our pool because of its mechanism that is different from other pool cleaners and admitted that other brands of pool cleaners were working fine with our pool because they used a different mechanism. We asked therefore if we could have it writting as asked by the retailer that they will only refund us after kreepy krauly gave the go ahead. Now when i do a follow up as to whats they way forward i get no responses and my messages go unanswered. We have a new pool cleaner that we not going to use and still under warranty and will not work with our pool and all we want is a refund so we can buy another brand that works well with our pool.