Business unit membership

Hello community, I hope you are well.

I'm trying to separate brands and lines of business with Business Unit Membership so that users who are part of a business unit have access to all assets and data within those business units, but still members of other lines of business They can see the assets of other lines of business.

I followed the steps in all the documents:
https://docs.oracle.com/en/cloud/saas/marketing/eloqua-user/Help/SecurityGroups/Tasks/CreatingSecurityGroups.htm

https://docs.oracle.com/en/cloud/saas/marketing/eloqua-user/Help/SecurityGroups/Tasks/CreateBusinessUnit.htm

https://docs.oracle.com/en/cloud/saas/marketing/eloqua-user/Help/SecurityGroups/Tasks/AssignGroupBusinessUnits.htm