html5 - font awesome not working inside a tag -

i have simple code. font awesome not working on it.

<a data-bind="click: someaction, attr: {id: 'sample-'+ $index(), href: 'sample-'+ $index()}, text: name" class="list-group-item" data-toggle="collapse">                     <span style="float: right"><i class="fa fa-plus"></i></span></a> 

i have correct version of font-awesome installed. if write span tag outside of a tag, can see plus sign want text , icon on same line.

it's little hard tell without live example, guess happens due floating span. try setting span-tag "display:block" or "display:inline-block". work when remove "float:right"?