S#.DATA (Hydra) Delete Data Function not working

I have about 500MB of 1minute TF Candles. When i use the DELTETE data function by selecting "ALL" and TF Candles - it works for a long time (15 seconds) but no data in disk actually gets removed. The storage folder is the exact same size before and after. I can also verify by pulling up any candle chart - they are still there. If i manually empty the storage folder then the data is gone and then candles no longer work. Screenshot shows how the function is used.

qusetions:

1. is this the correct behavior of the DELETE DATA function
2. if not, how should this tool be used?