My iPhone 11 has frozen, I have tried volume up volume down and trying to switch off but when asked to power down the phone does not respond

Hi Bicestersylvia,

Welcome to the Apple Community.

If you haven't tried it, try a "forced" restart of your iPhone:

Force restart iPhone – Apple Support

or

try getting in touch with the iPhone Support Team:

The iPhone Support team have a "Get support" link at the bottom of their website (link below)

iPhone - Official Apple Support

or

See if you can speak with someone from Apple in your country or region:

Apple phone numbers around the world

:Contact Apple for support and service - Apple Support

All the best :-)