Adjustment of Status - I-485

My state office is Kansas city. i am married to a US citizen, i applied for i-130, i-485 and EAD with USCIS. They received my application on 12/27/2016. i had my bio Feb 11 2017 and i had my interview on 04/03/2017. We were separated during the interview, our answer were similar up to 90%. We were told that a decision will be made and they will get back to us in 3 weeks time,no further documents was requested for. However, a decision has not been made ever since then, its been a year and 5 months after my interview and no decision had been made on my i130 and i485.My EAD has expired and i had renewed it. i have called several time and involved my congressman office but the responses had always been same. They claimed they are still conducting background check and its with another agency and they cant tell when it will be completed.