Possibly Failed Arizona Department Of Corrections Background Check?

Hi. For the past 4 or 5 months i was going through the hiring process to be a correctional officer for Arizona DOC. I ped the written test, fit pro test, drug test, psychological test, medical/physical test but im not sure if i ped the background check. The Background Investigations Unit called me last week asking about my previous jobs, criminal history, etc. I was honest to them about trying weed twice when i was 19 (Im 23 now) but have been clean ever since and i also had a juvenile record that was expunged by the the state of California. The guy who called me asked me about each offense that i had which most of them weren't filed...in other words i beat most of the cases except one for ault when i was 15 which i was sentence to probation until i was 18 but ended up getting off when i was 17 for good behavior and good grades in school. anyways they also asked me do i know or have i ever known any gang members. i said yes i do know gang members. growing up los angeles anybody/everybody is going to know somebody in a gang unless you live in beverly hills or malibu or somewhere. This is the main reason why im trying to relocate to another state. Tired of the violence and hearing about friends of mine getting shot. Anyways i was honest about everything. The background investigator told me if i get a call back from them then that means they thought i was lying about something so the next step would be taking a polygraph test. After that he said but if i get a call back from my recruiter then that means im ready to start the academy. A week later i got a letter in the mail saying that i was disqualified for one year for reasons unknown. i was confused because they said worst case scenario is that i would have to take a polygraph test to prove that i was telling the truth. I kept calling my recruiter for 2 days straight and nobody ever picked up the phone or returned back any of my calls. Can somebody please tell me why they think i was disqualified? I lost a lot of money going back and forth from long beach to arizona 4 or 5 times, calling off work, paying for rental cars, gas, and working very hard preparing myself for the fitness test. i just need an answer since they dont want to return my phone calls. I know this is a long explanation lol but please take the time to read it and respond. Thanks.