QB Issue Resolution:
Create a new Bank account and name it Clearing.
Use it for the Deposit account after processing the Customer Payment amount.
Now, use it to Pay the supplier.
The Clearing Account should always end at $0.
Resolution for Issue 'Pay an invoice with a bill or vice versa' available: Yes (Solved).
Source: Intuit Community forum.
Pay an invoice with a bill or vice versa: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for Bill
Quickbooks Repair Pro will resolve it efficiently and affordably. Guaranteed resolution of your issue, or you pay nothing!
Error Recovery for Bill [Canada]
E-Tech is the #1 Quickbooks data migration and Conversion service provider.
Additional Support Options: