my 13 pro max display was completely white what i have to do

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Re: my 13 pro max display was completely white what i have to do

Wondering what you were doing just before the iPhone froze (eg: updating / restoring / using an app / etc..

It may be just the app you were using that is frozen ? If so, try quitting that app.

How to: Quit and reopen an app on iPhone - Apple Support

If you still need help:

You may want to try re-starting your iPhone: Restart your iPhone - Apple Support

(eg: deletes temporary files, re-establishes connections, and often restores order if something is not working.

or

If you tried the tips in the "Related Article" above your question what happened ?

Also: Discussion thread on a similar situations with expert tips:

how to fix iPhone 13 white screen - Apple Community

else:

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

(online chat / phone / email etc.)

iPhone - Official Apple Support

All the best :-)