Datatype of the evaluated expression, <expression>, and the port datatype are not the same. Using default value of the port datatype as output. Change to: Expression datatype is not the same as the port datatype. Using a default port value to mask data.
The Integration Service could not apply a mask to a port configured for expression masking. The expression returns a result that is not the same datatype as the port in the Data Masking transformation. The Data Masking transformation returns a default masked value.
When you create an expression for a Data Masking transformation port, verify that the expression returns a value that matches the port datatype. The Expression Editor does not validate if the expression returns a datatype that is valid for the port.