I recorded a 20 minute session with my iPhone 11 Pro running ios 18.1.1. It was in 4K however, my phone had 130GB of free space! Halfway along the recording it displayed the error that my storage was full, and that recording stopped. I then proceeded to go to settings and check the storage, still 127 GB free. I have iCloud photos on, and my media is syncing.
We appreciate your interest in participating in the forums! These forums are for questions about developing software and accessories for Apple platforms. Your question seems related to a consumer feature and is better suited for the Apple Support Communities
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Albert Pascual Worldwide Developer Relations.