Hi,

The error message "External ID not found in the system" typically occurs when Odoo is unable to locate the specified external identifier (XML ID) in its database.

In your case, the XML ID gb_custom_hr.action_report_employment is not found in the system. This could happen for several reasons:

1)Double-check the XML ID to ensure that it is spelled correctly and matches the actual ID used in your code or configuration.

2)Verify that the XML ID is correctly defined in your code or data files. It should be defined either in a view, a menu item, an action, or any other relevant place.

3)If this XML ID is defined in a module, ensure that the module containing the XML ID is installed and properly loaded in your Odoo instance.

4)Ensure that you are referencing the XML ID within the correct scope. For example, if the XML ID belongs to a specific module, make sure you are referencing it within that module's context.

5) Make sure you have given the  XML id in the manifest before it is referenced or used in a different place

6)Upgrade your base module,accounting module and POS module

Hope it helps

I solved: in Account>> Configuration>>>Setting >> Reload Package Generic Chart Template 

Hi,
Try upgrading the account module instead of uninstalling and see if that solves the issue.

Thanks