Terrible service from Makro

On the 25th of June 2022 I made an online purchase for cooking oil from the Makro website. A few days later I was told that my order had been cancelled. I was offered a "voucher" which I can only use at Makro and instore only. I contested this because the reason I made the online purchase in the first place was that I find it convenient to do online shopping. Secondly, why would I be forced to use my money at Makro only, I found that distasteful and very condescending. It's only right that if you can't provide the service/product allow me to have a choice with the use of my money. For these reasons I insisted on waiting for the store to stock the product and deliver the goods to me once stock has been received by them. I have followed up with Makro and I either can't get through their call centre, on another occasion the call centre said it's the issue with the store and the store also directed me back to the call centre. The last time I got close to being assisted (via the chat) I was promised that this will be looked into. Nearly a month later I still have not received a response to Makro and they still have my R700.