What can I do?!

I purchased an ebook online for this book analysis I have to do for one of my classes, and once the purchase was complete I was told I would receive an email link to the ebook so I could download it but it's been 3 days and I have yet to receive anything. I sent two messages to the customer support and another email just now requesting a refund for the book I payed for but never received. If I don't hear back a third time, is there anything I can do? Maybe contact my bank and request  a refund there? I really don't wanna be out $10 ☹️☹️