My Flower App — Birthday item delivery fraud

I ordered a birthday cakes and flowers for my mother's birthday and as I wanted it to be delivered on time I paid extra fee for priority delivery from the website called myflowerapp. However, my mother didn't recieved the items it's been a day and the time they provided for delivery has passed almost a day ago. I tried reaching out to them however, there is no number to call. I tried mailing them and they told me your order has been delivered even though my mother never recieved anything. I tried explaining the situation and they just stopped answering to my mails. This seems to be a fraud. My mother was not well hence I wanted to make her feel better but now I have paid for nothing.