The basic type & cannot be created as a successor to &

What causes this issue?

Possible Causes:
As customer, you want to create a successor for an SAP basic type.
The namespace prefixes of the successor and the predecessor do not
agree with one another
The predecessor basic type was not created originally in this system

System Response

How to fix this error?

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Choose a different predecessor basic type or another name for the
successor.

Error message extract from SAP system. Copyright SAP SE.