NO REFUND AFTER TAKING MY MONEY AND NOT DELIVERING A TICKET!!!!

I purchased a ticket for Avengers Endgame on the 2nd of April 2019. Money was deducted but I didn't receive my ticket as their banking crashed. Up to now I've still not been refunded. I sent a mail with my details for the refund and received a reference number as per their instruction and I've phoned 3 consultants who keep giving me **** reasons why it's taken so long and then promise me I'm on the list for the bank and it'll take 3 work days. To date nothing has happened. They don't even respond to my follow up mails. I want someone who knows what is what to phone me and resolve this asap or i will take legal actions for theft.