Qliksense charts dissapeared

[Anonymous]

Hi,

I created a sheet full of charts and it worked great. But now, after some time, sheet is blank and I can't edit or add any chart or data in sheet editor.  Also thumbnail of the sheet contains "charts" that should be on the sheet but the sheet is empty. Can anybody please help me?

Thank you and best regards!

Blank sheet:

I can't add any chart on sheet, it just won't drop there:

Sheet's thumbnail showing shat should be presented on the sheet: