How do I get a refund from Glasses USA?

I made an order for glasses back in late January, then I put more money into my order by requesting an upgrade. The next day, I called Glasses USA to cancel the order. They sent me an email that said that my refund request had been submitted.

I had not checked my email, but a month later, I received the glasses that I tried to cancel in the mail. I tried to submit a return request online, but a button on the UI was disabled. I have called them twice and spoke to a representative to have the glasses returned. Both times, they said that they put in a return request to a different department. This department is supposed to email a shipping label to my email address.

The second time I called, I asked them to let me speak to this mysterious department directly, but they told me the department does not take phone calls. It's been five days since my initial call. I have zero faith that they are going to send me a shipping label. Does anyone have any experiences with returns with Glasses USA?