Please use the wage type copy function (transaction PU30)

What causes this issue?

If you continue, you will only generate the new or copied entry in
table T512W and will only determine the valuation for the new wage
type.

How to fix this error?

If you want to set up a complete wage type for payroll, copy an
existing wage type using the transaction PU30 (wage type copy
transaction). The transaction can be accessed via the Implementation
Guide (IMG) under Payroll (int.) --> Basic Settings --> Environment of
Wage Type Maintenance --> Create Wage Type Catalog (choose 'Copy').

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