Error in controller RootController

The application could not run because of the following error:

Details

Type: TiWare\Exception
Message: invalid json: Syntaxfehler, ung├╝ltiges JSON
File: /webroot/vendor/tiware/tiware-lib/Controller.php
Line: 849

Trace

#0 /webroot/vendor/tiware/tiware-lib/Controller.php(779): TiWare\Controller::fromJSON('')
#1 /webroot/vendor/tiware/tiware-lib/I18N.php(37): TiWare\Controller::loadJSON('cache//i18n.de....')
#2 /webroot/vendor/tiware/tiware-lib/RootController.php(192): TiWare\I18N->config(Array)
#3 [internal function]: TiWare\RootController->TiWare\{closure}()
#4 /webroot/vendor/slim/slim/Slim/Slim.php(386): call_user_func(Object(Closure))
#5 /webroot/vendor/tiware/tiware-lib/RootController.php(197): Slim\Slim->configureMode('development', Object(Closure))
#6 /webroot/vendor/tiware/tiware-lib/RootController.php(25): TiWare\RootController->run(false, Array)
#7 /webroot/index.php(6): TiWare\RootController->__construct()
#8 {main}