Assign the unit of measure to one characteristic only

What causes this issue?

You have set the indicator for the unit of measure for several process
instruction characteristics. However, the unit of measure can only be
displayed for one characteristic of a process instruction at a time.

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?

Set the indicator for the unit of measure for one process instruction
characteristic only.

Error message extract from SAP system. Copyright SAP SE.