Why is my Excel sheet not saving with new formatting or changes I have made?

1. Verify the correct file name and location on your computer.
2. Check to make sure that the correct file format is saved (.xlsx or other applicable file type).
3. Check for any errors or conflicts with the file format.
4. Make sure you have adequate permissions on the file.
5. Ensure that no other programs are accessing the same file.
6. Attempt to save the file to a different location.