Thanks for joining this thread, @rolo50. You can use any vendor for your journal entry, as long as it's correctly associated with the accounts and amounts. 

Also, you can only use the vendor's name if you're posting the entry to the Accounts Payable (A/P). However, if you're assigning it to the Accounts Receivable (A/R) and want to use the vendor's name, you'll need to add the vendor as a customer with a slightly different name. This way, you can choose it when you create the journal entry. In this process, we recommend consulting with your accountant to ensure the accuracy of your books.

In case you need to reverse or delete a journal entry, you can refer to this article for guidance: Reverse or delete a journal entry in QuickBooks Online.

If you have any follow-up questions regarding journal entries, please leave a comment below. We're always here to help you. Have a great day!