Slim Application Error

The application could not run because of the following error:

Details

Type: ErrorException
Code: 8
Message: Undefined property: App\Models\WPObject::$series?
File: /var/www/vhosts/folkartmuseum.org/beta/app/models/Programs.php
Line: 327

Trace

#0 /var/www/vhosts/folkartmuseum.org/beta/app/models/Programs.php(327): Slim\Slim::handleErrors(8, 'Undefined prope...', '/var/www/vhosts...', 327, Array)
#1 /var/www/vhosts/folkartmuseum.org/beta/app/models/Programs.php(106): App\Models\Programs::add_series_data(Object(App\Models\WPObject))
#2 /var/www/vhosts/folkartmuseum.org/beta/app/models/Programs.php(18): App\Models\Programs::get_programseries_posts(Object(App\Models\WPObject), Array)
#3 /var/www/vhosts/folkartmuseum.org/beta/app/routes.php(226): App\Models\Programs::get_program_info(Object(App\Models\WPObject), 'free-music-frid...', Array)
#4 [internal function]: {closure}('free-music-frid...')
#5 /var/www/vhosts/folkartmuseum.org/beta/vendor/slim/slim/Slim/Route.php(462): call_user_func_array(Object(Closure), Array)
#6 /var/www/vhosts/folkartmuseum.org/beta/vendor/slim/slim/Slim/Slim.php(1326): Slim\Route->dispatch()
#7 /var/www/vhosts/folkartmuseum.org/beta/vendor/slim/slim/Slim/Middleware/Flash.php(85): Slim\Slim->call()
#8 /var/www/vhosts/folkartmuseum.org/beta/vendor/slim/slim/Slim/Middleware/MethodOverride.php(92): Slim\Middleware\Flash->call()
#9 /var/www/vhosts/folkartmuseum.org/beta/vendor/slim/slim/Slim/Middleware/PrettyExceptions.php(67): Slim\Middleware\MethodOverride->call()
#10 /var/www/vhosts/folkartmuseum.org/beta/vendor/slim/slim/Slim/Slim.php(1271): Slim\Middleware\PrettyExceptions->call()
#11 /var/www/vhosts/folkartmuseum.org/httpdocs/index.php(51): Slim\Slim->run()
#12 {main}