We have no value at all in this outlet why the inconsistency

I have bought material in this outlet from foundation up to the roof finishing. I used an account which belongs to my mother who had made an arrangement with the shop that purchases can be made by either me or my father. Of the countless thousands weve spent in that shop I am now refused to buy fitting of a JoJo tank bought the same week in the same store. I am not happy at all about the inconsistency displayed following spending thousands in this shop. This incident is the final nail in the coffin. For me to get deliveries has been a night mare the staff has to be followed up more than necessary to be assisted. If I could i could return all their material and they bring the money since I'm no longer valuable. Yes the acc is not mine but how did they allow me to buy all along and spend so much when they were told the acc holder is unable to travel distances all the time. How pathetic and typical