Characteristic value for characteristic & in row block & is not unique.

What causes this issue?

You maintained several intervals and/or single values in the row block
&v2& for the characteristic. In doing so, at least one value appeared
more than once or two intervals overlap.

System Response

This causes the data records belonging to it to be used more than once
in the Report Writer, that means that they are referred to more than
once in the row or that subtotals are entered twice.

How to fix this error?

If the situation described is undesirable, maintain the characteristic
values in such a way that the data does not appear more than once.

Error message extract from SAP system. Copyright SAP SE.