Error [ERR_MULTIPLE_CALLBACK]: Callback called multiple times

node-red-contrib-oracle-ng throws an error when giving anser through http like if it would be receiving more than one msg but i can not see them with msg node.
It says:
Error [ERR_MULTIPLE_CALLBACK]: Callback called multiple times
And no more details is provided...
I checked node configuration "Output" which is set to "one msg/query", but I also tried "multiple msg/query"
