Task &1 in task group &2 requires a document type

What causes this issue?

No <DS:GLOS.document_type>document type</> is assigned to
<DS:GLOS.task>task</> &v1& in <DS:GLOS.task_group>task group</> &v2& in
<DS:GLOS.version>consolidation version</> &v3&.

System Response

Processing terminated

How to fix this error?

Assign a document type to this task in consolidation version &v3&.

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