zp_?

I have a problem with the ZPS and I would like their review. tube first mistake was that I could not buy more than 30 boxes (proof control) had 29,114 zp, buy two * 2 * Promotions 10000 zp zp = 9114, then buy 5 boxes zp 5500 = 3614, then buy 1 box 1000zp M14EBR zp = 2614 then try to buy one box of patriot and I came out of the same error point shot, now I have only 214 should be 2614 zp when someone can explain this? ***** I needed zp 2400 *** that's what happened? thanks for your reply.