Hi @Anonymous,
Do you add multiple Attachments Data cards within your Edit form?
Do you want the multiple Attachments Data cards value to be submitted to one record of your SP list?
Currently, within PowerApps, we could only add single one Attachments control within the Edit form. In addition, the Upload functionality of Attachments control only work in Edit form.
If you want to add multiple Attachments Data cards within your Edit form, and submit attachment files to your SP list, I afraid that there is no way to achieve your needs in PowerApps currently.
Actually, if you want to upload multiple files to one record of your SP list as attachments, you could add/upload multiple files within the single one Attachments control.
More details about the usage of Attachments control in PowerApps, please check the following blog:
https://powerapps.microsoft.com/en-us/blog/add-attachments-to-sharepoint-lists/
More details about Attachments control, please check the following article:
https://docs.microsoft.com/en-us/powerapps/maker/canvas-apps/controls/control-attachments
Best regards,
Kris