Posting is only possible with a zero balance; correct document Message no. F5060

We are getting the message Posting is only possible with a zero balance; correct document

Message no. F5060,while doing vendor invoicing after applying taxes and trying to rounding the credit amount to vendor.If we put the exact amount showing on balance field,system will save the entry.My concern is we want to ROUND OFF THE AMOUNT WHICH IS GOING TO CREDIT TO VENDOR.

Please advice