Hi @Jean Marie Baran
Permissions are not synchronized in real time. When you grant new permissions to a multi-tenant application in your tenant, these permissions are not synchronized to your customer tenants that use the multi-tenant application. You must run the admin consent URL in the browser and contact the global administrator of your customer tenant to sign in and consent to these permissions.
https://login.microsoftonline.com/{the id of your customer tenant}/adminconsent?client_id={client id}
Hope this helps.
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