Live text is a great feature in iOS 15 that allows iPhone to quickly recognize text and select, copy, paste and search in both the Camera and Photos app. This is a great feature that will even select handwriting and recognize text. You can use Live Text app with camera app, Photo app. Live Text can also read the Text in your photos, sorting photos by location, scene, people, objects and more.
However, many iPhone users are reporting issues with Live Text OCR in iOS 15 not working or misreading text.
Why Live Text doesn’t work on some iPhone, iPad models in iOS 15:
Please note that Live Text Support is supported on some limited iPhone models; Basically, Live Text feature requires iPhone with A12 bionic chip. Live text is a deep neural network and relies heavily on the neural engine. Therefore, only those with a capable neural engine support A12 and above.
Therefore, iPhones with iPhone X and older versions will not support live text. The following iPhone list will support live text feature
iPhone 13, 13 Mini, 13 Pro, 13 Pro Max.
Phone 12, 12 Mini, iphone 12 Pro, 12 Pro Max.
iPhone 11, 11 Pro, 11 Pro Max. XS, XS Max. XR.

How to turn on Live Text in iPhone Camera App: -In iPhone On Setting -Scroll down and tap on Camera. -Open Live Text -Force close the application and restart the camera application -It is useful to use the feature.
How to open Live Text in iPhone Photo App:
-In iPhone On Setting -Tap on General -Scroll down and tap on Language & religion. -Enable Live Text -You can now scan any photo for text in the Photo App o Open any photo in iPhone’s Photo app o At the bottom of the screen there will be a live text icon (three line viewfinder square) o Tap on it and it will scan any text in the photo.

Fix 1: Change region settings
iOS 15 Live text feature is limited to some regions or countries. If the live text feature is not available in your country, try changing the region/language in iPhone settings.
-Open iPhone settings -Tap General->Language & Region -Set language to English and region to USA for testing purposes.
I hope this will work for you.
Fix 2: Hard reset iPhone
Live text feature is a new feature in iOS 15 and there may be some software bugs if it is not working properly for you. A hard reboot to the iPhone should fix this. Please follow this guide to learn how to reset different iPhone versions.