lack of information from BSSV, any suggestion?

HI :  I am new in BSSV.  try to use SOAPUI to test the few BSSV ( add/change Voucher , add/change PO ).   Connected to BSSV to "get" is no problem but I run into many issue due to either missing/unexpected value for element in payload.. For example, this one : "CAUSE . . . . Your G/L distribution amount does not balance to the distribution amount calculated by the program."...  I also have similar issue in add PO WDLS..

I spent two days so far to research and try different possbile solution and still no luck.  Not able to understand which element should have what value and their relationship are very frastructed..