When trying to apply the license key from the Broadcom portal entitled 'VMware Aria Suite Standard 8.x for vSphere Foundation' there is an ERROR 'The following license keys are not valid, expired, or already exist and must be removed from your input before you can continue'.
Aria Operations
Please confirm you adding license the way explained in documentation for VMware Aria Operations License Keys
add license from : Subscriptions -> legacy licenses -> click on ADD