Complain about there service

They backlist me and my ITC was bad and l paid them the whole amount that the have requested. Then after 2 months l was looking for a job, they took my cv and call me to write a tast then l pass that test they told me that the will check my ITC then after will come for interviews. Day after l received a call from that company they said my ITC is bad so l won't get the job. I called Avon and told them they must update my ITC score cause now l can't find the job. They told me that the will do that within 21 day form last year till now l didn't receive any think form they side and l called them many times no respond. I called them again last week Thursday l ask for a confirmation letter that l don't owe them anything they said its will take 24 hours, l didn't receive any even now so l don't know what to do l'm stack now please help me.