$stateParams parameter undefined - angularjs

Question

I have the following routing:
$stateProvider
.state('message', {
parent: 'admin',
url: '/message',
templateUrl: './app/gol88/admin/messaging/page/list.page.html',
controller: 'ListController as listCtrl'
})
.state('replyMessage', {
parent: 'message',
url: '/{ticketId:int}/reply', //this should have {id} as stateParams
onEnter: ['$mdDialog', '$state', function($mdDialog, $state) {
$mdDialog.show({
controller: ReplyController,
controllerAs: 'replyCtrl',
templateUrl: '/app/gol88/admin/messaging/page/dialog/reply.html',
parent: angular.element(document.body),
clickOutsideToClose:true
}).then(function(response) {
}, function() {
$state.go('message');
});
}],
onExit: ['$mdDialog', function($mdDialog) {
$mdDialog.hide();
}]
})
;
When I tried to navigate to replyMessage state for the first time and use the $stateParams.ticketId in my Controller I am getting the value. However, when I transitioned to message state , and try to transition to replyMessage state back again, the $stateParams.ticketId is now undefined. Why is that so?
This is my controller for replyMessage state:
var ReplyForm = require('../model/reply_form.model');
ReplyController.$inject = ['$stateParams', 'TicketApiService'];
function ReplyController($stateParams, TicketApiService) {
var vm = this;
vm.ticket = null;
vm.ReplyForm = ReplyForm;
vm.addComment = addComment;
init();
function init() {
console.log($stateParams.ticketId);
/* TicketApiService.details($stateParams.ticketId)
.then(function(response) {
vm.ticket = response;
})
;*/
}
function addComment() {
TicketApiService.addComment($stateParams.ticketId, vm.ReplyForm.toPayload())
.then(function(response) {s.
vm.ticket.comments.unshift(response);
vm.ReplyForm.reset();
})
;
}
}
module.exports = ReplyController;