What am I missing?!? (long)

[oklahoma]

We have requested payment records from CSD a few times in the past and have copies of their records through May 2004.  In the past, I have just looked through the payments to make sure all that we had record of were listed on their records.  Then I looked at the bottom of the summary sheet to see the total amounts billed, paid, and owed.

Well, today we got a statement/June bill for CS, and the arrears amount was nowhere near what I had calculated.  So I sat down and started looking at the papers again.  I AM SO CONFUSED!!

There are columns for "amt sup billed" "amt sup recd" "diff btwn recd/paid" "amt sup paid" and "date."  They are listed in chronological order--more or less--and after each year there is listed a Year Total and Case Total for each of the above columns.

OK.  So first of all, I am wondering why there is a difference between amount recieved and amount paid?  I understand that they can charge interest on arrears, but NONE of our monthly statements have indicated any interest charged or any other fees, and yet for the case the total is $277.80.

Secondly, I noticed that the numbers on the summary sheet are different from the numbers listed in the above-mentioned columns.  i.e. the Case Total listed on every page is different from the total amounts listed on the last page.

Thirdly, I took the numbers CSD provided for "amount billed" and "amount paid" for each year, totalled them up, and came up with completely different numbers than either the case totals or the last page totals.

Fourthly, when I look at the differences between the Case Totals and the totals on the summary sheet, the gap is increasing--in February 2003 the "amt billed" was off by $1804 in May 2004 it was off $3202; in February 2003 the "amt paid" was off by $266.15 in May 2004 it was $1410.92.

What am I missing??  I WILL be calling/writing CSD soon (they also did not record a pretty hefty payment from last month--seized from our account, so it's not as if the check got lost in the mail.)  But I was wondering if ya'll had some explanations for this complete nonsense??

Maybe if the numbers were off a few dollars, or even a few hundred... but we are talking a few thousand--and almost $1300 difference in what I calculated my husband owes in arrears--which of course is the key figure right now.

Thanks in advance for any and all suggestions.