How can i retrieve the missing sheet on my libreoffice excel.

I updated the file last night and then today when i open the file to check some of my data in their, the sheet is gone and a new sheet created, named as “sheet6”. Please do help me, the file is so important and i dont know what happen

Do you have backup file? How did you update sheet: entering data or copying it from somewhere? Which operating system, which LO version?