how doI ghet mymoney back?

hello, I can’t find an address to email thisCompany and I paid for a download that is not what I had hoped. I just wanted to remove my vocals from my discs to make it vocal free to sing with it . I had a stroke and am blind and can no longer play guitar hence the reason for to mute my vocals from my songs. This won’t work, i have tried to open Knockout that won’t open, I upgraded to the new version, that is the same as the old version to me. How do I ask for my money back with a promise from me to remove this from my computer. I just want a simple vocal erasing software, not a mixing sound effect programme, I CAN’T SEE TO USE IT.
Can anyone help? Please

To try and get your money back you will need to contact the person or company that you paid.
Audacity is free, open source software and you did not purchase it from us as Audacity is a free download from here:

If you use Windows, Audacity 2.0 has pretty good compatibility with screen readers and most of the functions are accessible from the computer keyboard.
There are some resources specifically for blind users on the wiki here:

Thank you so much, I appreciate your reply.