Adding Excel export button hides/removes the Page Length Dropdown

I have just started using the Data Tables.
The Page Length Dropdown comes by default while implementing the DataTable.
Recently I added the Excel Button (export feature).
The issue is that adding this button hides/removes the Page Length Dropdown.

Is there a way where we can display both the features (i.e. the button and the dropdown) as I want to implement both of this feature?
Would changing the location of these controls solve the issue and how?

Here's my sample JS code :

$('#example).DataTable(
         {
             responsive: true,

             "lengthMenu": [[10, 25, 50, -1], [10, 25, 50, "All"]],     // page length options

             dom: 'bfrtip',
              buttons: ['excel']
         });

Thank You.