Only received partial order without any explanation

On 25 May I ordered 6 bottles of wine (Tierhoek) and a power bank (order number: ***. I received a notification that my order was ready for collection (this was after the restriction of no-alcohol was uplifted). I picked up my order at Clicks Honeydew, and could immediately see the wine was not there, only a small parcel containing the power bank. I have emailed One Day Only and then received a generic email response indicating that the wine might have been dispatched later. I have now waited for several weeks and there has been no further delivery. In fact, on my profile it states that I received the order, while the truth is that I only received the power bank. I have requested a refund for the wine but have not heard anything from One Day Only. There is no call centre number, only an email address. The customer service is terrible.