Hi ZoninV,
That’s very odd. It appears that your data contains incorrect information. Could you please try the following:
1) In Ticktory File->Settings->Dukascopy Data Store, remember the current setting and save it in notepad or another text editor. You can revert back to this setting once you have completed the remaining steps.
2) Select a new folder location for the Data Store information and press OK.
3) Display the chart again for June 2015 to August 2015.
Does this fix the problem? If so, it appears your data was somehow corrupted and it is recommended you delete the EURUSD directory in your original Data Store location and download it again.
Please let us know how you go.
Regards.