BIP2935
Severity
20 : Error
Message
(<insert_1>, <insert_2>) : An expression which evaluates to a scalar variable or a field is required here.
Explanation
The expression supplying the parameter must evaluate to a value of a suitable type. The given expression cannot possibly do so.
Response
Correct the syntax of your ESQL expression in node <insert_1>, around line and column <insert_2>, then redeploy the message flow.