- Text symbol &1: Invalid reference to control characteristic &2

What causes this issue?

The process instruction contains text symbol &V1& that refers to a
control characteristic. However, the process instruction assistant only
supports text symbols with characteristic numbers if they refer to
message characteristics.

System Response

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

If the control characteristic is used only once in the process
instruction, the text symbol is processed correctly in the process
instruction assistant.
If the control characteristic is used more than once, the system
creates a text symbol referring to the first use of the characteristic
when you exit the PI assistant.

How to fix this error?

If the control recipe is used more than once, carry out the following
steps to suit your requirements:
Delete the text symbol.
Correct the text symbol on the characteristic overview when you have
exited the process instruction assistant.

Error message extract from SAP system. Copyright SAP SE.