Terrible online store experience

Zero stars would be a fairer representation of the experience I’ve had ordering online with Sportscene. I placed an order for a pair of New Balance sneakers on the 21 March 2020. The web store stated there were 3 pairs of my size (UK7) in stock. On the 25th my order was reversed due to “insufficient stock or damaged goods”. I phoned their customer service hotline and was informed that the store does not update stock live and they did not have stock at the warehouse. This was then shortly reflected on the website. A few days later on the 31st, the website showed that there were 2 pairs of my size in stock again. I assumed that since stock had been updated online that maybe they had in fact found the previously listed stock. I emailed the TFG online store and enquired as to whether they did indeed have stock and it was confirmed to me that they did have stock of that specific model in my specific size. As soon as I received confirmation I ordered my size again. I received the general emails regarding my payment etc and all seemed well. Lockdown had just begun and during lockdown I had received an email that said that my order had been received, and another email stating that my order was safe during the lockdown period and would be delivered as soon as it was possible to do so. Today I received a message stating that due to lockdown delivery will be delayed but they will let me know when my item has been handed over to the courier. Upon clicking the view order button in the email I see my order has been returned? A few minutes later I receive an email that says “ We're so sorry to tell you that we have not been able to source one or more of the products in your order p*** placed on 31 March 2020. We have tried to find it in several stores, but due to high demand, we were not successful.” PLEASE explain to me how after stock was confirmed, my order was confirmed and after my order was confirmed safe during lockdown have I not received my goods for a second time? How can my order be safe if there is no stock or it hasn’t been sourced? How can you confirm that you’ve received my order and that delivery will be delayed due to lockdown if you haven’t even got stock? I’m disgusted and as a long time supporter of your store, since 2008 and today is the absolute last day you will see my business.