Awaiting a refund since September 2017 for convention that was never done

After numerous emails I cannot get a hold of anyone at this company. The contact number I have is ********** . It continuously rings, there is no answer. We paid for a convention that was supposedly to have taken place in September, but it never did. We paid for it in advance. It was never done so we asked for a refund. We filled inn a credit information sheet and sent it through to them on the 11th October 2017. Since then three different individuals at my place of work, have tried to get a hold of them and no one has succeeded. I am hoping that this complaint will get me a response today.