Did you try use that KB? There are few additional steps.
Thank you for your ask.
Could you tell me something about your Infrastructure. Which Strategy Backup do you use? Some of Backup Strategies need to have an node/proxyVM inside OLVM (please look at that Documentation page: https://storware.g*tbook.io/backup-and-recovery/protecting-virtual-machines/virtual-machines/oracle-linux-virtualization-manager in example Disk Attachment need an proxyVM)
Please tell me, did you follow our guide in Documentation? https://storware.g*tbook.io/backup-and-recovery/deployment/installation (You could use all in one, where configuration is minimal)