Reset comment on next candle

I created a comment based on a certain condition, but i wanted it to reset on next candle so it's only visible when the condition is met. Seems simple but it's over my league.

Any help appreciated.

the code:
....
CrossUp[i] = EMPTY_VALUE;
if (trend[i] !=trend[i+1])
if (trend[i] == 1)
CrossUp[i] = Low[i] - iATR(NULL,0,20,i)/2.0;
data=Symbol()+"UP";

}
Comment(data);
.....

On the next candle, if conditions don't meet:

thanks

You're welcome!