fetching page's tab and adding tab to the facebook pages by graph api method fb.api() result in error

I am making user to log in my app with 'manage_pages' permission by the call to

FB.login(function(response) {...... },{scope:'manage_pages'});

I want to add my app tab to a user page.I fetch all the pages of the user with the call to

FB.api('/me/accounts?access_token=ACCESS_TOKEN','get', function(response){......},{scope:'manage_pages'});

Now after fetching the all pages I let the user to select a page which he wants to add my app tab to.

when user select开发者_如何学C a page I make a call to the method

FB.api('/PAGE_ID/tabs?appId=myAppId&access_token=page_access_token_fetch_by_above_method', 'post',function(response) {........});

but method return error as response, response is:

/**/ FB.ApiServer._callbacks.f17a44c23({"error":{"message":"(#210) Subject must be a page.","type":"OAuthException"}});

even tabs fetching on a page with the following call result in same error:

FB.api('/PAGE_ID/tabs?access_token=page_access_token_fetch_by_above_method', function(response) {});

For me it was working like this:

    FB.api('/me/accounts', function(response) {
        if (!response || response.error) {
            alert('Facebook get accounts error occured ' + response.error);
        } else {                    
            var pageData = response.data;
   /* looking for the right page specific access_token */
            FB.Array.forEach(response.data, function(onePage) {
                if( onePage.id == page ) {
                    access_token = onePage.access_token;
                }
            });
   /* adding the app to the page */
            FB.api(page + '/tabs', 'POST', { app_id: app, access_token: access_token }, function(response) {
                if (!response || response.error) {
                    alert('Facebook add app error ' + response.error);
                } else {
                    alert('App has been added');
                }
            }); /* end of page/tabs*/
        }
    }); /* end of /me/accounts */

I hope it helps.