I had a not exactly the same thing when returning a bass to them that I just didn’t get on with. I dropped it off personally and the first thing said was “it’s got Rotosounds on it, they’re not the stock strings”. My reply was they were the strings that came on it - which they were. They then tried it out, tested it etc, and finally relented and reimbursed. Did make me think about purchasing online from them again.