If you scheduled a job to run automatically and checked "Retry failed VMs processing" checkbox, VBR should perform the retry.
Note that VBR does not perform automatic retry for jobs started manually by design. VBR does not perform a retry if a job session has finished with the Success or Warning status. During the job retry only those VMs that have failed will be processesed. If your case doesn`t apply to any of these cases, please contact Veeam Technical Support team.