Rounding issues when trying to match bank transactions

Hi

I am trying to match one payment to multiple bills in bank transactions. One bill is to be paid in full and the other will be partially paid.  I keep getting the following error.

There are one or more errors: A rounding issue has occurred on a line where the amount has been manually adjusted. Please delete the line, add a new line, and try again

I have tried following instructions from previous posts for this problem but it is not working. I have deleted and re-entered the invoices, I have checked for decimal places that are more than 2 places, I have tried going to purchases and record a supplier payment and also tried to record payment from the bill. I still can not get the bill to match. 

your assistance would be appreciated

thanks

Lisa