Data won't show when using datepicker as query param - angularjs

Question

I want to set value of query params with a datepicker, but when I try it the data won't display. I have include ng-model into my query params but doesn't work.
Here is my .js file, I want to pass dt and dt2 into query params in http get
app.controller("repcont", ['$scope','$http',function($scope,$http){
$scope.open1 = function() {
$scope.popup1.opened = true;
};
$scope.open2 = function() {
$scope.popup2.opened = true;
};
$scope.setDate = function(year, month, day) {
$scope.dt = new Date(year, month, day);
$scope.dt2 = new Date(year, month, day);
};
$scope.formats = ['dd-MMMM-yyyy', 'yyyyMMdd'];
$scope.format = $scope.formats[0];
$scope.popup1 = {
opened: false
};
$scope.popup2 = {
opened: false
};
$scope.cari = function () {
$http.get('......./rpt?a='+$scope.dt+'b='+$scope.dt2).then(function(response){
$scope.report = response.data;
here is my .html file
<div class="col-md-2">
<p class="input-group">
<input type="text" class="form-control" uib-datepicker-popup="{{format}}" ng-model="dt" is-open="popup1.opened" />
<span class="input-group-btn">
<button type="button" class="btn btn-default" ng-click="open1()"><i class="glyphicon glyphicon-calendar"></i></button>
</span>
</p>
</div>
<div class="col-md-2">
<p class="input-group">
<input type="text" class="form-control" uib-datepicker-popup="{{format}}" ng-model="dt2" is-open="popup2.opened"/>
<span class="input-group-btn">
<button type="button" class="btn btn-default" ng-click="open2()"><i class="glyphicon glyphicon-calendar"></i></button>
</span>
</p>
</div>
<button type="button" class="btn btn-primary" ng-click="cari()"> Search </button>
</div>
</div>
<div class="jarak">
<table class="table table-bordered">
<thead>
<th>Tanggal</th>
<th>Jumlah Bayar</th>
<th>Jumlah Failed</th>
<th>Jumlah Closed</th>
<th>Jumlah Unflag</th>
</thead>
<tbody ng-repeat="item in report">
<tr>
<td>{{item.paydate}}</td>
<td>{{item.sumpaid}}</td>
<td>{{item.sumfail}}</td>
<td>{{item.sumclose}}</td>
<td>{{item.sumflag}}</td>
<p>Total Rows : {{report.length}}</p>
</tr>
</tbody>
</table>
Here is the result of my report: