I am using scanner but it is giving message Your script generated an error, while code is copied from “https://zerodha.com/expert-advisors/code/bullish-engulfing-with-ema”
Code: EMA(CLOSE,9)<EMA(CLOSE,21) AND
REF(CLOSE,1)>REF(OPEN,1) AND
REF(CLOSE,2)<REF(OPEN,2) AND
REF(OPEN,1)<REF(CLOSE,2) AND
REF(CLOSE,1)>REF(OPEN,2)
Please suggest what to do