There is 'Message displayed on credit memo' in credit memo, which field in CreditMemo object that store this info??

I'll be glad to help share some information about the Credit Memo, userkchen.

Both fields will show the information you've entered on a specific report depending on how you filter it. 

You can refer to the screenshots I've attached for visual reference:

For Journal Report within the Credit Memo, only the field below stores the information. See attached screenshot:

To learn more information about multiple filters to customize your report, please refer to this article: Customize reports in QuickBooks Online.

Post anytime here if you have any additional concerns. We're here to help.

I am using SDK to develop transaction into QBO.   All I really want to know is something like a data field within the credit memo object that, for example, like XXXXXX below that I can assign a value to it and that value will display on 'Message Display on Credit Memo' 

CreditMemo creditMemo = new CreditMemo();

creditMemo.DocNumber = "my doc number";

creditMemo.XXXXXX = "My message to display on Credit Memo";

Thanks for getting back to us, @userkchen.

I know the right support team who can handle your software development kit (SDK) concern. 

We have a separate community for application developers that can help you develop credit memo transactions using SDK. From there, you can interact with experienced users, engineers, and other experts who are willing to share their insights and best practices about it.

First, you can browse through the SDK resources as your guide. Here's how to proceed:

1. Go to this link: Intuit Developers.
2. Click API Docs & Tools at the top.
3. Select QuickBooks Online, and then SDKs.
4. Choose your preferred SDKs language.
   
5. If you need further help, click the question mark icon at the top.
6. Select QuickBooks Online, and then Ask a Question.
   
7. Choose Sign In or Create Account, and then follow the on-screen prompts to continue.

After that, you're now ready to apply your customer credits to handle them effectively.

Do you still have more questions about credit memos in QuickBooks? Feel free to add them below. I'd be around to assist you always.