Guitarzoom.com — Purchase of an online course charged for twice

https://support.guitarzoom.com
I purchased an online guitar course called 36 Accoustic Guitar Licks from Guitar Zoom. I live in the UK. The checkout process (paying by PayPal) didn't complete because I hadn't filled in the STATE field (because I have no US state) and it wouldn't proceed until I did fill it in - so I used the UK county name instead. Subsequently I received TWO confirmation emails for the subscription and checked my Paypal account where there were two charges made for the same amount. The email confirmation had a link to get into the site with the guitar course material. I use a password utility program to keep track of site access and the password got saved to there. I sent an email asking for one of the charges to be refunded and got an email back with a link to a "ticket" response to my complaint. Clicking on this I got asked for a password to see their response - entering the password I have for access to the site course didn't work. So I sent another request which resulted in another message with link to another ticket - and the password to access that still doesn't work and they won't send me a password that does work. So we go round and round and it all takes up endless amounts of time. Musically the material is good bout the IT aspects of the admin in this company are poor. all they have to do is send me an email with the information I asked for but they resort to giving me links to responses that I can't read. And I still don't have the refund.