Issue with Data source setting

Hi NorahTran97 ,

Thanks for reaching out to Microsoft Fabric Community.

The error “A child can’t be both removed and included” generally occurs when the metadata structure between the connected semantic model and the report becomes inconsistent - for example, when tables, fields, or relationships are modified or removed in the model after it was connected in Power BI Desktop.

As you mentioned that you’re unable to edit or add new tables from the same semantic model, please try the following steps:

1. Open Power BI Desktop, go to File > Options and settings > Data source settings, and select Clear Permissions for the semantic model connection.

2. Close and reopen the file, then reconnect to the semantic model from Get Data > Power BI Datasets.

3. If the issue persists, try connecting to a copy of the same dataset published in a separate workspace to rule out any corruption or broken reference in the metadata.

Hope this helps. Please reach out for further assistance.

Thank you.