Asked to keep quiet by manager

I have been buying bra's and taking it back as the ribbing on the bra comes loose or something. Today I returned bra 's at your canal walk store the manager asked me thrice to take something else unfortunately I need bra's. She raised her voice also when presented with the photo of my slip rather than the actual slip. For 2 years I have had back and forth with all miladys stores also I take a picture of my slip as I usually loose the original but from previous area management was advised if the slip is emailed to the store they can still assist as it has a transaction number and also your store manager at Canal walk refused to assist. Luckily I looked threw my wallet again and found the slip mind you that your store manager and I had words and this lady tells me that I must keep quiet before she says something to me. Excuse me? I don't keep quiet on demand and especially not to your untrained, unpleasant and unprofessional staff. I want the area manager to contact me and his superior. Every time I step into miladys canal walk the unpleasant experiences flows in.