This issue is triggered when you have a picture uploader on your Bubble page, and the checkbox "Make this file private" is not checked.
When this checkbox is left unchecked, it means that all the pictures uploaded through this picture uploader will be public. If you're uploading invoices, ID documents, or estimates, you probably don't want them to be accessible to everyone.
Solution
In order to fix this issue, the only thing you have to do is to check the "Make this file private" checkbox and link it to the according data type. Like this:
