Page Layout Format Automatically Copies to Other Worksheets After Grouping Worksheets

Thank you for your response, however, I am aware of all of these steps and successfully performed them for years until this past week. Something has changed in the functionality of Excel, not only for me but for others as well. The problem is that the formatting is being automatically changed upon grouping the worksheets. I am not making any changes to the worksheets while they are grouped. The formatting of the worksheet that I am on when grouping them is being automatically applied to the others. Even if I group the other worksheets first then add a worksheet, the formatting gets applied to the worksheet added last based on the one that is visible when the group is created. As a result, I cannot print a group of worksheets in which any of the worksheets has a different formatting than the others. I also can't change the start number of a group of worksheets that have page numbering.