BIP2482
Severity
20 : Error
Message
(<insert_1>, <insert_2>) : The dynamic field reference does not resolve to a valid reference.
Explanation
The dynamic field reference supplied must resolve to a decalred variable or a message field. Uninitialized references are not acceptable.
Response
Correct the syntax of your ESQL expression in node <insert_1>, around line and column <insert_2>, then redeploy the message flow.