Midland Credit Management, Inc Checks not being cashed when sent, changing the arranged payments and sending me statements saying that they didn't receive payment in 35 days, noting a phone number that is not connect to the company, and voice mail being full. Los Angeles California

It was about 2013 when I got my first stsement from Midland Credit Management, Incorporated and I did try to make arrangements on paying them.  I first sent them a money order on March 01, 2013 and they got that.  I decided to send a check on April 01,2013 and waited to see if it showed up in my bank account.  I knew something was not right when I did not see that check.  I then got a statement that they did not see a payment in 35 days.  I called them immediately and chewed them out telling them that I did pay and it was in a check.  The kept on asking for the check number and I did not give them a number because it was suspicious to me for any one to ask that.  I told them I could only pay $15.00 a month and that if they could not arrange it there would not be anymore paymnts made. when they re-arranged my payments I told them that if they changed the arrangements again that I was not going to deal with hem anymore.  I sent them another check on May 01, 2013 and it is not showing again that it was not cashed.  I also am concerned because the number they are having me to call was a different number than the company number.  The number that I called was (888) 327-0001 and I was under the impression that this was a ligitimite numbr but when I called on the weekend It was naming a different company altogether and the voice mail was full.  Can you se what is going on for me please.  Am I being scammed?  Apparently tey cannot cash the checks because it is in the company's name.  I know they got the checks I had them sent thugh the post office.  The other address where they are having the checks and money ordrs sent to is:P.O. Box 6058, Los Angeles, CA  90060-0578.  Please help me!  I do not want to be scammed any more.  Please investigate this for me.