After changing VCF Operations/Aria Operations Root and Admin from the GRUB menu following KB How to Reset the Root Password for VCF Operations you are unable to log into the Admin UI of Aria Operations due to an invalid credential error.
VCF Operations/Aria Operations
The password was reset on the PhotonOS local user instead of the Application-level user.
Reset the Application-layer Admin account password:
$VMWARE_PYTHON_BIN $VCOPS_BASE/../vmware-vcopssuite/utilities/sliceConfiguration/bin/vcopsSetAdminPassword.py --reset