Operation sign for numerical values

What causes this issue?

The entry in the field <ZK>"Sign of the operation"</> is incorrect
In this case a numeric value corresponds to a ZADIG element code.

System Response

The system interrupts the processing.

How to fix this error?

You have the following options for the operation that you would like to
perform:
a blank, which cancels the data corresponding at that moment to the
<ZK>"Zadig element code"</> and replaces it with a value entered into
the zone <ZK>"Corresponding data"</>;
a "+" to add these two values;
a "-" to deduct these two values from each other.

Procedure for System Administrators

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

Error message extract from SAP system. Copyright SAP SE.