iPhone and MacBook shutting off too quickly

This is not Apple Support, it is a fellow user-supported public community where no Apple employees participate.

Contact Official Apple Support in the manner you did previously and provide your case number. We simply have no access to internal Apple content.

Shutting off... as in you have to press a power button to turn them on again?

Or are you describing a display on / off mode? Or sleep mode, or...?

Set sleep and wake settings for your Mac - Apple Support

Keep the iPhone display on longer - Apple Support