Let me assist you in adding a donor successfully while creating a bill, @BPRCtreasurer.
In QuickBooks Online (QBO), donors are added as vendors when setting up and recording in-kind donations.
If you're unable to add an existing donor as a vendor, it could be due to identical names. You can differentiate them by adding a middle initial, for example.
Also, you can keep track of fund donations received via credit card, bank transfer, or cash by referring to the article: Track funds you receive from donors in QuickBooks Online.
Let me know in the comments below if you have any other QBO-related concerns. I'm always willing to help. Take care and have a good one!
