Scanner code is required

hello, traders
i want a code for inside candle (high and low of candle is less than previous candle ) on intra day chatrs.
i used following code for above condition.
high<ref(high,1) and low>ref(low,1)
time frame 30 mintute and 10 days(sacnner setting)
but when i using this code first 30 minute signal are generated but t after first 30 minute no signal is generated even condition are match on intraday chatrs
please guide

If the scanner works, it will work throughout. Have you tried sorting the alerts on descending chronological order?