bootstrap datepicker format changes automatically on select textbox

i have used format like mm/yyyy for date picker in ember as following,

$('#fromdatetimepicker').datetimepicker({

    format: 'MM/YYYY',
    showClose: true,
    showClear: true,
    keepOpen: false,
    sideBySide: true,
    maxDate: maxDate
  });

but on click of date textbox for second time the format changes like mm/dd/yyyy automatically.pls help me to resolve it