Viator is a ****

I made a booking on the 03 October 2023( reference number 1071177417) , but I realised that I selected the wrong date.I immediately cancelled the booking.I received a cancellation confirmation from Viator and they mentioned I will receive my refund within 3-5 business days.Now they are giving me a runaround , they are telling me that the problem is with my bank. I contacted my bank yesterday and they told me that they didn’t receive any payment from Viator. .I asked them to send me the proof of payment but they sent me an email saying that they refund was processed on the 3rd of October 2023.It feels like they are ****ming me. I demand an immediate refund.They are ******.