XF 2.2 ErrorException: Template error: [E_USER_WARNING] Cannot call method isOnline on a non-object (NULL) src/XF/Template/Templater.php:1169 Generated by: U

[husham memar]

Please could someone help me .. I am trying to find out what this error showing in my admin page in the error section.
here is an output of the details

#0 [internal function]: XF\Template\Templater->handleTemplateError(512, '[E_USER_WARNING...', '/home/forumadmi...', 1169, Array)
#1 src/XF/Template/Templater.php(1169): trigger_error('Cannot call met...', 512)
#2 internal_data/code_cache/templates/l1/s2/public/message_macros.php(186): XF\Template\Templater->method(NULL, 'isOnline', Array)
#3 src/XF/Template/Templater.php(817): XF\Template\Templater->{closure}(Object(XF\Template\Templater), Array, NULL)
#4 internal_data/code_cache/templates/l1/s2/public/post_macros.php(25): XF\Template\Templater->callMacro('message_macros', 'user_info', Array, Array)
#5 src/XF/Template/Templater.php(980): XF\Template\Templater->{closure}(Object(XF\Template\Templater), Array, Object(XF\Template\ExtensionSet))
#6 src/XF/Template/Templater.php(916): XF\Template\Templater->renderExtensionInternal('user_cell', Array, Array, Object(XF\Template\ExtensionSet))
#7 internal_data/code_cache/templates/l1/s2/public/post_macros.php(146): XF\Template\Templater->renderExtension('user_cell', Array, Object(XF\Template\ExtensionSet))
#8 src/XF/Template/Templater.php(980): XF\Template\Templater->{closure}(Object(XF\Template\Templater), Array, Object(XF\Template\ExtensionSet))
#9 src/XF/Template/Templater.php(916): XF\Template\Templater->renderExtensionInternal('full_body', Array, Array, Object(XF\Template\ExtensionSet))
#10 internal_data/code_cache/templates/l1/s2/public/post_macros.php(178): XF\Template\Templater->renderExtension('full_body', Array, Object(XF\Template\ExtensionSet))
#11 src/XF/Template/Templater.php(817): XF\Template\Templater->{closure}(Object(XF\Template\Templater), Array, Object(XF\Template\ExtensionSet))
#12 internal_data/code_cache/templates/l1/s2/public/thread_view.php(795): XF\Template\Templater->callMacro('post_macros', 'post', Array, Array)
#13 src/XF/Template/Templater.php(1644): XF\Template\Templater->{closure}(Object(XF\Template\Templater), Array, Object(XF\Template\ExtensionSet))
#14 src/XF/Template/Template.php(24): XF\Template\Templater->renderTemplate('thread_view', Array)
#15 src/XF/Mvc/Renderer/Html.php(48): XF\Template\Template->render()
#16 src/XF/Mvc/Dispatcher.php(458): XF\Mvc\Renderer\Html->renderView('XF:Thread\\View', 'public:thread_v...', Array)
#17 src/XF/Mvc/Dispatcher.php(440): XF\Mvc\Dispatcher->renderView(Object(XF\Mvc\Renderer\Html), Object(XF\Mvc\Reply\View))
#18 src/XF/Mvc/Dispatcher.php(400): XF\Mvc\Dispatcher->renderReply(Object(XF\Mvc\Renderer\Html), Object(XF\Mvc\Reply\View))
#19 src/XF/Mvc/Dispatcher.php(58): XF\Mvc\Dispatcher->render(Object(XF\Mvc\Reply\View), 'html')
#20 src/XF/App.php(2344): XF\Mvc\Dispatcher->run()
#21 src/XF.php(512): XF\App->run()
#22 index.php(20): XF::runApp('XF\\Pub\\App')
#23 {main}

I would apprecaite if someone can help me understand what this is all about. and I am sorry I dont have much knowldge of things but I did the folowin
Rebuild the addon
removed unessery addons
removed all styles except for one
rebuil the caches one by one.. not even sure if that helps this or anything

I searched the forum but no one has a clear answer on this .. would appreciate some direct instructions please