Hello ajgreymo,
Welcome to Apple Support Communities!
If we understand your post correctly, you're trying to sync your phone with your Mac but get a message that the selected device could not be found. We'd like to help!
"Look in the Finder or iTunes
On a Mac with macOS Catalina or later, look for your device in the sidebar of any window in the Finder.*
On a Mac with an earlier version of macOS, look for your device in iTunes.
On a Windows PC with iTunes, look for your device in iTunes.
Learn more about viewing your device on a computer
Update the software on all devices
Update your iPhone or iPad
Update your Mac
Connect your device directly to your computer
Make sure that your device is unlocked and showing its Home Screen, then use a USB cable to connect it directly to a USB port on your computer. Don't connect to a USB hub or other device.
If that doesn't help, unplug your device and all other USB devices and accessories from your computer. Then reconnect only your device.
Trust your computer, if asked
When you plug your device into a your computer, if you see a “Trust this Computer?” alert on your device, tap Trust.
About the 'Trust This Computer' alert
Restart your devices
Restart your iPhone
Restart your Windows PC
Try a different port, cable, or computer
The issue could be related to your computer, its USB port, or the USB cable connecting it to your device. If possible, try a different computer, USB port, or USB cable.
Contact us
If your computer still doesn't recognize your iPhone or iPad, contact Apple Support."
If your computer doesn't recognize your iPhone, iPad, or iPod
Thank you for using Apple Support Communities.
Take care!