Phone frozen . Can’t unlock it

Try a force restart. Press and very quickly release the volume up button, press and very quickly release the volume down button, then press and hold the side button for about twenty seconds. When the Apple logo appears, release the button. The timing is a little tricky, so try it a few times.

Force restart iPhone - Apple Support

If a force restart can't be done, it's a hardware issue. You'll have to contact Apple for support or take it in to a Genius Bar or Apple Authorized Service Provider (AASP).

Find Locations - Apple

Contact - Official Apple Support

See the Apple Support article(s) below. Link to contact Apple Support in the article.

iPhone won't turn on or is frozen.  *

ASC YouTube for how to restart your iPhone if it’s frozen on the Apple logo

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