Welcome to the QuickBooks Community, @Skottydawg1. Let me assist you with the attachments to your invoices and estimates.

At times, QuickBooks Online encounters unexpected behavior, such as files automatically detaching from transactions due to accumulated cache and cookies. In the meantime, I recommend using a private browsing window that doesn't store files. Browsers use cache and cookies to load web pages faster.

To open an incognito window, you can refer to these keyboard shortcuts:

• Google Chrome: Press Crtl+Shift+P
• Microsoft Edge & Mozilla Firefox: Crtl+Shift+N
• Safari: Press Command+Shift+N

If you can now attach your images without disappearing in a specific time, consider returning to your regular browser and clearing its cache and cookies.

If you still have the same result, I suggest utilizing another supported browser. It can help us identify if the issue is specific to your current browser.

Moreover, you can check this article to learn more about attachments: Add or delete attachments in QuickBooks Online.

Let me know if you still have questions about your attachments. Have a great day, and take care.