This transaction is not a business expense so it does not hit the P&L

create an asset account called due from [name]

create a service item for the service you are paying and select that due from account on the item screen

enter the bill and use that item in item detials, or use that account in the account details, and enter the amount, pay the bill.  The due from account total will increase with each payment

invoice the customer and use that item on the invoice, when the payment is made the due from account balance will lower.