Why can’t I update my xr even after connecting WiFi

Hi ogiesoba

Welcome to the Apple Community.

Wondering which iOS version you are updating from, and to ...

and if you are getting an error message that would help determine the cause.

Eg:

You may need to also be plugged in to power to update.

or

You may need to ensure you have enough free storage space for the update on your iPhone.

How to check the storage on your iPhone, iPad, and iPod touch - Apple Support

or

Apple support have trouble-shooting articles online that may help:

If your iPhone or iPad won't update - Apple Support

If you can't update or restore your iPhone or iPod touch - Apple Support

If you see an error when you update or restore your iPhone, iPad or iPod – Apple Support

All the best :-)