Thanks @christiano_ben.
Are you able to upgrade your instance to the latest patched version of 2.41 (2.41.9: DHIS2 patch release 41.9 is now available)? This would be a general recommendation, and might fix the issues you’re experiencing with the organisation unit tree in the data entry app.
If that’s not possible, we can try to help debug some more. A 2.41.0 instance should not be accessing the api/organisationUnits/gist when rendering the organisation unit tree, but to rule that out, could you check the requests that get fired to any endpoint like organisationUnits when you load the app
e.g. in the network tab:
You may also want to check the payload at api/organisationUnits?fields=id,displayName and check that displayName is coming through.