It sounds like you may have some merged cells or hidden columns in your spreadsheet that are preventing you from expanding the selection when sorting. Here are some steps you can try to troubleshoot the issue:

1. Check for merged cells: Merged cells can cause issues when sorting, as they can prevent the selection from expanding properly. To check for merged cells, select the entire spreadsheet by clicking the box in the upper left corner of the worksheet (above row 1 and to the left of column A). Then, go to the Home tab and click on the Merge & Center button in the Alignment group. If the button is grayed out, there are no merged cells in your spreadsheet. If it is active, click on it to unmerge any merged cells.
   
2. Unhide any hidden columns: Hidden columns can also prevent the selection from expanding properly. To check for hidden columns, select the entire spreadsheet by clicking the box in the upper left corner of the worksheet (above row 1 and to the left of column A). Then, go to the Home tab and click on the Format button in the Cells group. From the drop-down menu, select Hide & Unhide and then click on Unhide Columns. If any columns were hidden, they will now be visible and you should be able to expand the selection when sorting.
   
3. Try sorting one column at a time: If you are still having issues expanding the selection when sorting, try sorting one column at a time. First, select the column you want to sort and click on the Sort button. In the Sort dialog box, select the options you want and click OK. Then, select the next column you want to sort and repeat the process. This may be a bit more time-consuming, but it should allow you to sort the columns you need without any issues.

I hope these suggestions help you resolve the issue you are experiencing when sorting your spreadsheet. Let me know if you have any other questions or if there is anything else I can assist you with.