Dimension &1 does not have a document type with initial posting level

What causes this issue?

Dimension &V1& does not have a document type with initial posting level
(<LS>Realtime Update</>). However, the following functions require this
document type for processing:
Data transfer method <LS>Read from Universal Document</>
Validation of universal documents

System Response

You cannot execute the above functions in dimension &V1&.

How to fix this error?

In dimension &V1&, create a document type with initial posting level (
<LS>Realtime Update</>).

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.