Add More Storage
More storage can be added to your account based on your plan: Pricing - Additional Storage (at the bottom of the chart).
If you choose this option, no further action is needed on your part.
We'll automatically upgrade your plan to get you under the limit. This means we'll either include a storage add-on or upgrade you to the next plan level, whichever is cheapest.
Note: A plan can have a maximum of two storage add-ons. Beyond that, the plan will be upgraded.
Get Under the Limit
You can remove files and/or images from your apps to get under the limit.
As you remove files/images from an app, be sure to clear unused storage assets from your account dashboard: Clear Unused Storage Assets. This will ensure that files and images are completely deleted so that your storage amount is lowered accordingly.
If you want to store those files/images locally before deleting them, you can export and download them: Batch Download All of the images and Files In My App.