If I bought extra cloud space why is my phone still running out of space?

So what is the point of me buying extra ICloud space then?

Nobody here can answer that question for you.

I need the extra room on my device

Your device's storage can't be upgraded.

Some iCloud features will help reduce the storage required for photo content on your device.

see >>> https://support.apple.com/en-ca/HT205703

Because the types of storage are separate and not part of the same pool.

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