My client has lots of digital products in Her store (PDF -files). I have a few questions for those who have also this situation.
1. How much can upload files to Shopify (settings-> files)? I have uploaded the images to the store and it shows already that I cannot upload more:
2. Do you have digital products stored outside of Shopify? And when the customer buys your product it sends the product(s) to the customer's email?
If you're seeing that banner remain for what feels like a longer than normal timeframe I would suggest contacting Shopify Support.
It's possible you're seeing a bug so worth the team looking into it. Be sure to have that message ready to hand over to the support person you talk to.