Slim Application Error

The application could not run because of the following error:

Details

Type: TypeError
Message: Argument 1 passed to Projects::nextProject() must be an instance of Project, null given, called in /www/htdocs/w00a8593/www.acuteacute.com/app/lib/routes.php on line 38
File: /www/htdocs/w00a8593/www.acuteacute.com/app/lib/Projects.php
Line: 217

Trace

#0 /www/htdocs/w00a8593/www.acuteacute.com/app/lib/routes.php(38): Projects->nextProject(NULL)
#1 [internal function]: Closure->{closure}(Object(Slim\Http\Request), Object(Slim\Http\Response), Array)
#2 /www/htdocs/w00a8593/www.acuteacute.com/app/vendor/slim/slim/Slim/Handlers/Strategies/RequestResponse.php(40): call_user_func(Object(Closure), Object(Slim\Http\Request), Object(Slim\Http\Response), Array)
#3 /www/htdocs/w00a8593/www.acuteacute.com/app/vendor/slim/slim/Slim/Route.php(281): Slim\Handlers\Strategies\RequestResponse->__invoke(Object(Closure), Object(Slim\Http\Request), Object(Slim\Http\Response), Array)
#4 /www/htdocs/w00a8593/www.acuteacute.com/app/vendor/slim/slim/Slim/MiddlewareAwareTrait.php(117): Slim\Route->__invoke(Object(Slim\Http\Request), Object(Slim\Http\Response))
#5 /www/htdocs/w00a8593/www.acuteacute.com/app/vendor/slim/slim/Slim/Route.php(268): Slim\Route->callMiddlewareStack(Object(Slim\Http\Request), Object(Slim\Http\Response))
#6 /www/htdocs/w00a8593/www.acuteacute.com/app/vendor/slim/slim/Slim/App.php(503): Slim\Route->run(Object(Slim\Http\Request), Object(Slim\Http\Response))
#7 /www/htdocs/w00a8593/www.acuteacute.com/app/vendor/slim/slim/Slim/MiddlewareAwareTrait.php(117): Slim\App->__invoke(Object(Slim\Http\Request), Object(Slim\Http\Response))
#8 /www/htdocs/w00a8593/www.acuteacute.com/app/vendor/slim/slim/Slim/App.php(392): Slim\App->callMiddlewareStack(Object(Slim\Http\Request), Object(Slim\Http\Response))
#9 /www/htdocs/w00a8593/www.acuteacute.com/app/vendor/slim/slim/Slim/App.php(297): Slim\App->process(Object(Slim\Http\Request), Object(Slim\Http\Response))
#10 /www/htdocs/w00a8593/www.acuteacute.com/app/index.php(11): Slim\App->run()
#11 {main}