Hi loderscomputers,
Thanks for contacting Apple Support Communities!
We understand that your photos chosen to use with your Contacts are too large and don't quite fit.
If you're unable to adjust the size of the photos using the Photos app editing tools, you can install extensions to use with Photos to help you to edit your photos to make them smaller so they will fit: Edit with third-party apps and extensions in Photos - Apple Support
"Install iOS apps that offer extensions
Use the App Store on your device to find and install apps that allow full editing from Photos or include extensions for Photos. Apps that include Photos extensions often say so in their descriptions; search for terms like "Photos extension" to explore more apps.
You can also choose from the apps listed in Edit Images Faster With Photo Extensions on the App Store."
We hope this helps.
Cheers!