The easiest fix is by using the provided script to add permissions sets to your admin application role. It is documented in https://docs.oracle.com/en/middleware/bi/analytics-server/security-oas/grant-or-revoke-permissions-assignments.html

And you can also look at https://support.oracle.com/ic/builder/rt/customer_portal/live/webApps/customer-portal/?anchorId=&documentId=KB399022&page=sptemplate&sptemplate=km-article that covers the same as yours. Look at the "Solution" part of the page, the "for example" mostly. It use the script linked above and give you an example of what it should look like for the admin application role.

This should fix your issues (it is also one of the post-migration task in the doc, maybe worth also checking your other default application roles as they will also be missing or missing permissions, for those you use the same script and can reference https://support.oracle.com/ic/builder/rt/customer_portal/live/webApps/customer-portal/?anchorId=&documentId=KB546502&page=sptemplate&sptemplate=km-article for an example of what they should be like).

Overall, I always prefer to never restore the security model from a previous versions BAR when importing. You will always lose any new permissions added in the product, without an option to merge the new permissions with yours. I usually suggest to manage the security "by code", via WLST commands. This allow to merge new defaults with the custom security model required, and also allow auditing of who changed what and when if you version your scripts. But this is a different topic :D