You are trying to create a business rule on Blueprint but receiving an error "Cannot create a rule with invalid required attributes.".
Release : 16.1.2
Unfortunately, it is not possible to use a Required Fields rule on these data types:
You cannot enforce this rule on the following data types: Attachments, TSV, Calculated/Aggregated/Formula, Boolean, Read-only studio attributes, Auto Number fields. and Rich Text fields.
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