False routing in express.js

I am trying to use the following filter to divert packages but it fails: I've build to routes using express.js:

app.get('/billdetails/:year/:month/:phoneId', function (req, res, next) {
    var db = req.db;
    var year = req.params.year;
    var month = req.params.month;
    var phoneId = req.params.phoneId;
    async.parallel({...})

app.get('/billdetails/lastinvoices/:number/:limit', function (req, res, next) {
    var db = req.db;
    var number = req.params.number;
    var limit = req.params.limit;
    async.parallel({...})

So when i request the first URL everything works fine, but when I try to request the second route I get the same response as from the first one.

Does anybody know why this happens?

Regards and thank you.

via icodeweb