How do I free up my storage on my iPhone11pro plus? I bought extra storage on iCloud already. Buy a new phone?

Sorry, but these are the only ways to free up space on your iPhone:

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Free up space on your device

Using the steps above, you might see a list of recommendations for optimizing your device storage, followed by a list of installed apps and the amount of storage each one uses. Tap an app's name for more information about its storage. If you don't see any recommendations, try these steps:

• If you use iCloud Photos and turn on Optimize Storage, you can lower the amount of storage that your photos use on your device. 
• You can remove content from your apps like photos, music, and podcasts. 
• You can delete apps that you're no longer using.

Learn more about how to optimize the storage on your iOS or iPadOS device.

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copied from: What's the difference between device storage and iCloud storage? - Apple Support