Stax Souns great doesn't honour their 7 day valid quotations.

I received a quotation from Derrick for the replacement of a tv by the insurance. I asked him how could he quote me on a special price, for the price can change if the claim takes time to pay out. He said I should just come to him and he will sort it out. He's quotation is valid for 7 days. He emailed the Quote on 1 March. I returned on 7 March and the salesmen I spoke to said I just missed Derrrik and should return the next day because insurance works with different prices. I asked him regarding the upgrade to a bigger tv that was priced R14999 and said Derrik will help me the next day. I returned the next day to find the same tv for R18999. Derrick said he couldn't help me and the prices went up during the night. I phoned the store manager Jacques/ Jaco and he said he couldn't help me and would return my call with an answer, after he spoke to his boss, the same day or the next morning, which didn't happen. I got hold of Derrik again the next day and now suddenly the 7 day valid quote is out of stock although they have the same tv in stock but with the inflated price.