Particulars relating to standard service catalog already exist

What causes this issue?

The standard service catalog data (type, edition, and item
number in the standard catalog) already exists in one or more other
service master records.

How to fix this error?

Please check your data. The item description in a standard service
catalog is usually unique, and the item may therefore only be
represented by one master record.

Error message extract from SAP system. Copyright SAP SE.