Data labels format in graphs always gone !!!

Dear users/technicians,

I have a problem in liberoffice calc. I have lots of column charts. I inserted the data labels for every column. I formatted the data labels for all charts, it took hours. I was frustrated when I closed the file that every format was gone when I opened it again. I did it once more for one graph, closed the file, opened it nothing saved.

How to solve this problem?

Hi

Could you clarify I inserted the data labels for every column. I formatted the data labels for all charts ?

When editing a chart the only thing to do is InsertData Labels

Regards

Do you saved as .ods?