Bad service at Sleepmasters

I purchased a mattress online on the 24th August 2021. Today is the 9th of September 2021 and have not received it as yet even though I selected delivery to take place in 3-10 days. I called their call centre once and they said they will follow up for me and gave me a reference number. Then a few days later I chatted with Lebo online and she told me that they did not have the mattress in stock but my concern is that no one has bothered to confirm or acknowledge my purchase nor bother to inform me that they don't have the mattress in stock. Why did their system allow me to proceed with the purchase if they did not have the merchandise in stock. This is beyond disgusting