False advertising/ Promotional discrepancy

On the 4/5/2020 i purchased coffee machine for R8999.00 The website said this item is on promotion so I bought it. On the 5/5/2020 I received an email confirming that my purchase was ready for collection and I collected it on the 6/5/2020 Today11/5/2020 I received their promotional email and the exact same machine is now on promotion for R7999.00 A whole R1000.00 less. I feel that I should be refunded the R1000.00 difference. I have spent 4 calls to them today and I keep getting cut off. If this item was on promotion then surely the price should have increased not gone on a promotion a few days later again at even less.. Something is very wrong here.