organization hierarchy error

 hi,

we are rolling out from one operating to multiple operating units.

after doing OU level setups in Oracle Projects, we are facing below errors:

error when trying to delete a link from hierarchy:

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app-pa-19052: you cannot delete/update link in hierarchy used by oracle projects

error when trying to move link between operating units in hierarchy:

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ora-20001: you cannot delete/update link in hierarchy used by oracle projects

cause: you cannot delete or update any hierarchy links of the organization hierarchy under the start organization specified for use by oracle projects

ora-06512: at "apps.hr_hierarchy_element_api"