Superbalist did not timely allocate my payment to my order, they decided to cancel it instead

I ordered shoes that were on sale on the 17th of August and paid for them on the 19th of August. On the 21th I checked my Superbalist.com account and realized the order had not been dispatched. I called them the same day and they asked me to send proof of payment so the funds can be manually allocated to my oredr. I sent the POP on the 23rd and advised them that the reference number that I had used was missing one digit. They acknowledge receipt of my email and resolved to escalate the matter to their Finance department for them to manually allocate my payment. My order was however cancelled on the 25th. Upon following up, they said payment was not allocated to my order. A Supervisor (whose name I wont mention here) followed up and said the show will not be restocked. Today I saw the same shoe in the same size advertised on their website but it was "on hold," therefore I could not buy it. Moments later it was sold to someone else. I'm really disappointed, Superbalist.com does not seem to respect nor value their customers.