Maximum number of columns (&) exceeded. Result is incomplete.

What causes this issue?

The maximum number of drilldown characteristics is restricted to &V1&.

System Response

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

How to fix this error?

Reduce the number of drilldown characteristics, by filtering according
to characteristics or dragging characteristics back into the free
characteristics.

Error message extract from SAP system. Copyright SAP SE.