Hi there, @garchard.

I'm glad you've reached out to the Community. Allow me to share some information on why you're seeing negative expense amount on your vendor's information. 

Bill transactions will show up as an expenses if you haven't applied them to a payment yet. Once you've paid the bill, the bill-payment will show a positive amount on both Account Payable (A/P) and the transaction bank accounts when you run vendor reports.

If this is a stock item, make sure to select an asset account on the posting account and not the expense account. 

You can also verify if the bill-payment was linked to the correct bill. If not, you' need to delete it and apply the payment to the correct one. 

Please let me know how it goes by clicking the Reply button below. I'll be around to further assists you if you have additional questions about the Account Payable cycle. Have a good day ahead!