Lo-Fi Games

I'm new to the forum but not to the game itself. I've had a blast playing around with the demo and I want to purchase the game through this site with BMT. The problem I get though is when I fill out all the information to buy it on the final part of the order form I get asked for a purchase order number which I have no idea what it is. Is there anyone that knows what the number is or do I have to request it???

Have you tried just leaving it blank?

Yeah I did it after checking to see if BMT would double charge me if it went through or not and it worked fine. Thanks for taking the time to at least try to help. I love the game and I hope it gets even better