Hi @DANAqs, welcome to the Zapier Community 
Thanks for reaching out and providing such detailed information about the issue you’re encountering with custom fields in QuickBooks Online Advanced (QBO) not showing up in Zapier.
From Intuit’s documentation, custom fields in QBO will only show in the API response if they meet specific criteria:
1. Field Type and Limitations:
• Only the first three string-based custom fields are included in the API response. Even if you have fewer than three, only string-based fields qualify.
• Since one of your fields is a number, it won’t appear in the API response. This restriction can cause Zapier to miss fields during configuration.
2. Field Availability:
• Custom fields must be enabled for all sales forms (like invoices, estimates, sales receipts) or all purchase forms. If they’re configured for specific forms only, they won’t appear in the API response.
3. Immutable Mapping:
• Even if custom fields are marked as inactive in QBO, their original mapping persists. This can create unexpected behavior if you’ve made changes.
I would suggest reviewing the above information and then retesting your trigger. If the issue persists, I would encourage you to reach out to our support team so we can dig deeper:
https://zapier.com/l/support
Hope this helps!
I am having the same issue. The custom field was setup as per the instructions above
Hi @zevi21! 
I’m so sorry to hear that you’re running into the same issue. I can see that @DANAqs reached out to the Support Team but there was no further response from them so I’m uncertain whether things were resolved. I see that you’ve also reached out to the Support Team, so I’d recommend continuing the conversation with them directly via email. They’ll be able to dig into the logs for your Zap to help determine why those custom fields still aren’t appearing.
Keen to ensure this gets sorted so please keep us in the loop on how you get on with them!