Formula.Firewall: Query 'X' (step 'Y') references other queries or steps, so it may not directly access a data source. Please rebuild this data combination.

The privacy firewall blocked one step that both touches a data source and uses values from another query.

Why it happens

• A single step combines a source connector with the output of another query.
• A dynamic source path (URL, file path, SQL) is built from another query's value.
• Data sources with conflicting privacy levels are being combined.

How to fix it

1. Split the work: one query accesses the source, a second does the combination — never both in one step.
2. Set consistent privacy levels, or turn off 'Combine data according to privacy level settings' for that file if appropriate.
3. Avoid passing another query's value straight into a connector function in the same step.