Hi Louise Pancholi,
Thank you for reaching out to Microsoft Q&A
Can you check if you have all the permissions mentioned in this document's Pre-requisite: https://learn.microsoft.com/en-us/azure/devops/boards/backlogs/organize-backlog?view=azure-devops#prerequisites
You need Basic access level assigned to yourself at Organization level.
Along with the Project Administrator and Team Administrator permission, can you check if you have Basic level access like below:
Visit your Organization Settings > In General Tab > Select Users > Search for yourself > Select ... dots > Change access level > Click on Basic and change your access to Basic.