Warning: require_once(conf/envvar_ts_dev.interface.php): Failed to open stream: No such file or directory in /htdocs/isograd_ts/phpclass/router/router.class.php on line 3

Fatal error: Uncaught Error: Failed opening required 'conf/envvar_ts_dev.interface.php' (include_path='/htdocs/isograd_ts/phpclass:/usr/share/php7/TOSA:/htdocs/isograd_ts/vendor/pear/pear-core-minimal/src:/htdocs/isograd_ts/vendor/pear/mail_mime') in /htdocs/isograd_ts/phpclass/router/router.class.php:3 Stack trace: #0 /htdocs/isograd_ts/vendor/composer/ClassLoader.php(444): include() #1 /htdocs/isograd_ts/vendor/composer/ClassLoader.php(322): Composer\Autoload\includeFile('/htdocs/isograd...') #2 /htdocs/isograd_ts/public/index.php(5): Composer\Autoload\ClassLoader->loadClass('Router') #3 {main} thrown in /htdocs/isograd_ts/phpclass/router/router.class.php on line 3