Data lost

Hi!
Few days ago I lost data on chart for tags who have History Provider “hodoseevka”:
screenshot.su/show.php?img=807c8 … 8522e9.jpg
When I ZOOMIN the chart I have this error:
screenshot.su/show.php?img=c4665 … 29abb9.jpg
screenshot.su/show.php?img=fe1a7 … d7af50.jpg

What the problem it is?
Help, please.