When I applied to their network, I had to show them other CPA networks I worked with and my earnings, and the traffic sources I got. It's the most I've had to go through to get accepted into a network, even harder than MaxBounty. The Affiliate manager kept going back and forth with me before letting me in and I got a lot of experience. So I can see why you might have not gotten approved. Try reaching out to them on the thread they got here.