Answer:
The answer is "check the worksheet is not read only"
Step-by-step explanation:
The read only mode is used for read the file data, and it doesn't allows the user to update the file, and for updating the worksheet we should check iut does not open in the read-only mode.
If it is open, then we close it and for close we goto the office button and click on the tools option after that goto general setting, in this there is a check box for turn off the read-only mode.