Sleepmasters is totally undermining me worst customer treatment!!

I recently bought 4 beds cash 2 queens and 2 single beds .I want to exchange the one queen for a king called the store Sleepmasters at Mall@ Carnival I spoke to Prudence told her I need to exchange the queen for king and the price diff she said its okay i can exchange and she will call me back with the price of the king size she calls to tell me "I have bad news the supplier wont take back the bed because the PLASTIC IS TORN so she will no longer exchange and also due to covid.

How is my query with the store have anything to do with the supplier, I then requested the manager she said she cannot give me the umber I requested the regional manager she said she is not allowed to give me the number other than the customer center. I'm extremely disappointed at how we treat customer and that we always have to fight to get attention only to realize that she is the store manager and doesn't want to refer me to her manager. I feel undermined I'm a customer paid cash for 4 beds really and still willing to get the king size from sleepmasters but is this the treatment I get.