Exception

Accessing user for writing when null in [/home/public/src/Utility/Auth.php, line 71]
#-1 /home/public/src/View/AppView.php(47)
#0 /home/public/vendor/pieceofcake2/cakephp/src/Cake/View/View.php(968): AppView->_evaluate('/home/public/sr...', Array)
#1 /home/public/vendor/pieceofcake2/cakephp/src/Cake/View/View.php(473): View->_render('/home/public/sr...')
#2 /home/public/vendor/pieceofcake2/cakephp/src/Cake/Controller/Controller.php(1004): View->render(NULL, NULL)
#3 /home/public/vendor/pieceofcake2/cakephp/src/Cake/Routing/Dispatcher.php(197): Controller->render()
#4 /home/public/vendor/pieceofcake2/cakephp/src/Cake/Routing/Dispatcher.php(163): Dispatcher->_invoke(Object(TagsController), Object(CakeRequest))
#5 /home/public/webroot/index.php(70): Dispatcher->dispatch(Object(CakeRequest), Object(CakeResponse))
#6 {main}