QB Issue Resolution:

open the vendor(supplier)  list

find the PO, enter a check mark in the box far left, use the drop down arrow on that line to create a bill – odd way to do it in my opinion

Resolution for Issue 'How do you change purchase orders into bills' available: Yes (Solved).
Source: Intuit Community forum.

How do you change purchase orders into bills: 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 box far
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Error Recovery for box far [Canada]
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