Serial numbers can be managed only if base unit of measure is discrete

What causes this issue?

You wanted to specify a serial number profile. However, this requires
the base unit of measure to be discrete (such as <LS>piece</> or
<LS>pallet</>). The unit of measure you have entered is not discrete
because it can be converted into other units of measure of the same
<DS:GLOS.3526C2A3AFAB52B9E10000009B38F974>dimension</> (for example,
kilograms to grams in the case of the dimension <LS>weight</>).

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?

Enter a base unit of measure that is discrete, that is, dimensionless.

Error message extract from SAP system. Copyright SAP SE.