Bad service

I went to American Swiss Eastgate to exchange an item bought from bash online and the service that I received was very bad especially from the lady that's a surpivisor. Firstly they said we need to return same way we brought the item which is bash as I did not have the invoice on email. We suggested that she uses order number and she refused. I then phoned bash customer care on my way home and the lady on the line was very helpful and even offered to contact the store. She told us that they can access the details via order number and they should assist. We drove back to Eastgate now with the invoice sent by the lady from bash online. Supervisor was not even interested to help and she was very annoyed. After spending another 30 minutes she said system doesn't allow her to void and she sent us home again. I am so disappointed by the service received.