get error in response - wamp.error.no_such_subscription

Question

there is WAMP - The Web Application Messaging Protocol (https_github.com/tavendo/WAMP/blob/master/spec/basic.md)

for back-end I use https_github.com/voryx/Thruway

for a front http_autobahn.ws/js/

OS - Ubuntu 12 without GUI set up by vagrant

there is - PHP 5.5.9-1 and composer for it.

I'm trying to use standart functionality of Subscribing and Unsubscribing I get "Unsubscribe ERROR" when trying to perform Unsubscribe

My subscribing is looks like:

this.subscribe = function(r,clientId){
        if (!chat.searchSub("loc.wampchat.room.message." + self.room_id)) {
            chat.transport.session.subscribe('loc.wampchat.room.message.' + self.room_id, function (args, kwargs, details) {
                self.addMessage(kwargs.message, kwargs.author_id, kwargs.create_time);
            }).done(function(subscription){
                self.subscriber['loc.wampchat.room.message.' + self.room_id] = subscription;
            });
        }
        if (!chat.searchSub("loc.wampchat.join.room." + self.room_id)) {
            chat.transport.session.subscribe('loc.wampchat.join.room.' + self.room_id, function (args, kwargs, details) {
                self.addUser(chat.connections[kwargs.user_id].user);
                if(kwargs.user_id == clientId){
                    r.add(clientId);
                }
            }).done(function(subscription){
                self.subscriber['loc.wampchat.join.room.' + self.room_id] = subscription;             
            });                
        }
        if (!chat.searchSub("loc.wampchat.leave.room." + self.room_id)) {
            chat.transport.session.subscribe('loc.wampchat.leave.room.' + self.room_id, function (args, kwargs, details) {
                self.deleteUser(kwargs.user_id);
            }).done(function(subscription){
                self.subscriber['loc.wampchat.leave.room.' + self.room_id] = subscription;
            });
        }
    };

the final topic ("loc.wampchat.room.message." + self.room_id) looks like "loc.wampchat.room.message.1125"

Its strange error because it's appears only for topic loc.wampchat.room.message.... and for all other topics (which are almost the same) all good!

Unsubscribing looks like:

for(var key in self.subscriber){
        chat.transport.session.unsubscribe(self.subscriber[key]);
    }

chat.transport.session - it's a simple global object where WAMP session is stored   

Here what console (in browser, Chrome-latest) shows to me:

1. WebSocket transport receive
    [8,34,6196960130236416,{},"wamp.error.no_such_subscription"]



 2. (autobahn.js:791) failing transport due to protocol violation:
    UNSUBSCRIBE-ERROR received for non-pending request ID
    6196960130236416



 3. (autobahn.js:4480) Uncaught InvalidAccessError: Failed to execute
    'close' on 'WebSocket': The code must be either 1000, or between
    3000 and 4999. 1002 is neither.     
        (autobahn.js:3010) transport.close      
        (autobahn.js:3129) self._protocol_violation  
        (autobahn.js:3648) self._process_UNSUBSCRIBE_ERROR  
        (autobahn.js:4451) self._socket.onmessage   websocket.onmessage

And the main misunderstanding that when this error appears server no react at all - simply continue to work! I do not see any problems in server log.

So the main question is : how critical is this error? Can I just forgot about it and continue my work or I MUST somehow fix it?