Error during component search; unit &1 does not exist

What causes this issue?

The concentration entries must be converted during the component search
if the search criteria were defined with a unit other than the
component concentration.
In addition, the percentage is converted to the unit used in the search
criteria, if the upper limit of the search interval is undefined.
The unit &V1& needed for the conversion does not exist in the System.

System Response

The search was terminated when the error occurred. The result is
undefined or incorrect.

How to fix this error?

Contact your system administrator and maintain the missing unit in
<ZK>Global Settings</> Customizing in <ZK>Check unit of measure</>.

Error message extract from SAP system. Copyright SAP SE.