Raspberry Pi OS • The following packages have been kept back?

Code:

sudo apt update && sudo apt upgrade -y

Code:

1 package can be upgraded. Run 'apt list --upgradable' to see it.The following packages have been kept back:  linux-image-rpi-v8:arm640 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.

Code:

z2@z2:~ $ apt list --upgradable -aListing... Donelinux-image-rpi-v8/stable 1:6.1.73-1+rpt1 arm64 [upgradable from: 1:6.1.63-1+rpt1]linux-image-rpi-v8/now 1:6.1.63-1+rpt1 arm64 [installed,upgradable to: 1:6.1.73-1+rpt1]