How can set caller person photo to full screen

Hello Prince9409,

Thanks for using Apple Support Communities! We see you have a question about the photo when a contact calls you, and we'd like to help.

With iOS 14, a smaller alert message was added: What’s new in iOS 14

"Compact calls Incoming calls, including FaceTime calls and calls from supported third-party apps, appear in an all‑new compact design that doesn’t take up the full screen."

You can change the setting so the call screen is back to being full screen. Go to Settings > Phone > Incoming Calls > Full Screen.

Take care!

The availability for some of iOS’s features is dependable on the accounts you use on the device to sync your data with. This applies to the size of a photo on a Caller ID screen.

This said, you will need to make sure your contact cards are stored on/synced with the account, that does not reduce the image/photo you assign to the contact card to the thumbnail size. From my own experience, I know iCloud Contacts keep full size image, while Google reduces the photo to the thumbnail size.