hbase scanner .next() returns null

I'm scanning the hbase for md5 string and I have to perform some actions, if there are strings found. The problem is, that if I check it first time, it returns true (and at log is the value), but then, when I use same expression in if or for statement I got a false result.

        Scan scanCookiesData = new Scan();

        scanCookiesData.addColumn(Bytes.toBytes("md5data"), Bytes.toBytes("md5data"));
        ResultScanner scannerCookiesData = dbHelper.getTable("userInfo").getScanner(scanCookiesData);
            if (scannerCookiesData.next() != null) {
            response.getWriter().println("if (scannerCookiesData.next() != null)");

            for (Result r = scannerCookiesData.next(); r != null; r = scannerCookiesData.next()) {
                response.getWriter().println("INSIDE FOR!!!");

                if (md5data.equals(Bytes.toString(r.value()))) {
                    // Here we will assign ID to the user.
                    response.getWriter().println(assignID(Bytes.toString(r.value())));
                    response.setStatus(200);
                } else {
                    response.getWriter().println("ELSE");
                }
            }
        } else {
            response.getWriter().println(createNewUser(json));
            response.setStatus(200);
        }

In this code, at first if it gets "true", but in for is not invoked, as it will show "false".. but scanner is not a null (in db is that md5 string), so it should get "true"..