STLM Histogram Indicator

Hi, I've download the STLM histogram indicator. I'm trying to use it to backtest on the daily chart but it's only providing data till 10th March 2021. If I go further back it's just blank. I'm currently back testing on EUR/USD. I've tried going into other currencies and I'm having the same issue, where it stops early 2021. I've also tried different times like H1 and it goes back as far as 16th Dec. I have a feeling there's a limit to the amount of data being displayed but I'm not sure how to reset this.