I am using the latest (7.0.4.2) but has occurred on many earlier versions as well. Simple bar charts disappear after saving and reloading document. It doesn’t seem to matter how many series - fails on one-series bar chart as well as multi-series line charts. Getting super frustrated. Have created new charts as well as have copied older charts from other worksheets and updated data locations. This is sucking bad. Please help me.
I would wager that your problem is caused by saving your document in a format different than Calc’s native format (.ods), perhaps .xls or something else. Wanna bet?
Winner, winner chicken dinner. I WAS saving it in .xlxs format. Redid charts and saved as .ods and when reopened document, they were there! So, good workaround, but there is still a bug - should be able to save in open xml format.
But saving in native format is not a “workaround”. It is a Best Practice for any software.
I am not familiar with the .xlxs format so you may have identified a bug. For directions please see How to Report Bugs in LibreOffice - The Document Foundation Wiki