Could not return a shower in a box,

I'm bought 4 showers for a project of mine, we opened 1 shower to fit and it could not fit 100% as it is not adjustable. Upon returning for an exchange, I was told by one of the sales men that Top T doesn't take returns that have been opened. I was shocked for life as this was not even communicated to me. The box is still in a reasonable state, it's just opened. I had tapes it back to secure the glass and parts. Care has been taken as I returned the shower, only to be denied a return of a brand new shower, never been used. The umber opened the shower only to see if it's adjustable. He didn't try to install it or any work done on the shower. Still in brand new condition. They didn't even inspect the shower. It's a lot of money gone to waste.