Zend certified PHP/Magento developer

Why are my organisations greyed out in IAM Identity Center?

I’m trying to set up an account with SSO in IAM Identity Center. I’m logged in as the management account but the checkboxes next to both the root node and the OU in the hierarchy are greyed out. My goal is to have an account that can provide access to the CLI via SSO, and I one test account (in addition to the management account) that I want to add to this OU.

What would you check to move forwards?

Thanks.

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Here is my test user:
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