No hierarchy level specified for object &.

What causes this issue?

No value is specified in the View cluster object structure for the
object &V1& in the field "Step".

System Response

The View cluster was activated nevertheless.

How to fix this error?

this field is only relevant for view clusters which still use a
navigation subscreen.
Enter a "Step" value which is a whole number between 1 and 10.
This value specifies the hierarchy level of an object in the View
cluster. A header entry is step = 1, an object which depends directly
on a header object is step = 2, etc.
The step affects the subscreen layout. The short descriptions are
indented appropriately, and a leading arrow indicates the dependency.
It has no further significance.
From Release 46A, the view cluster uses Tree Control navigation, the
"Step" field is not used and need not be filled. The message can be
ignored in this case.

How to fix this error?

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.