drop down id not getting if i give ng-repeat in mvc Angular

Question

am adding table row on changing of dropdown,

<tr ng-repeat="r in rvm" >

<td>

<select ng-model="Customer.ID" ng-options="c.ID as c.Name for c in customer" ng-change="GetAccountBalance($index)" style="width:150px;height:22px;" name=" tCustomer">

<option value="">Select Customer</option>

</select>

</td>

<td>

<input type="text" ng-model="AdjustAmount" name="tPendingAdjusted" />

</td>

<td>

<input type="text" ng-model="ReceiptsViewModel.AdjustAmount" name="tAmount" />

</td>

<td>

</tr>

JS

$scope.rvm = [{}];

$scope.GetAccountBalance = function (index) {

var getAccountBalance = ReceiptsService.GetAccountBalance($scope.ID);

var id = $scope.ID;

alert(id);

if ($scope.rvm.length == (index + 1)) {

$scope.rvm.push({

});

}

am able to add new row by using this code on dropdown change, but am not getting selected dropdown id(alert:undefined)

if i comment ng-repeat in tr , am getting id but not adding row

how to get id on ng-repeat