PHP Fatal error: Uncaught GuzzleHttp\\Exception\\RequestException: cURL error 3: <url> malformed

[Alexander]

PHP Fatal error: Uncaught GuzzleHttp\Exception\RequestException: cURL error 3: malformed (see https://curl.haxx.se/libcurl/c/libcurl-errors.html) for /api/tokens in /var/www/html/guacamole-php-sdk/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php:211\nStack trace:\n#0 /var/www/html/guacamole-php-sdk/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php(158): GuzzleHttp\Handler\CurlFactory::createRejection(Object(GuzzleHttp\Handler\EasyHandle), Array)\n#1 /var/www/html/guacamole-php-sdk/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php(110): GuzzleHttp\Handler\CurlFactory::finishError(Object(GuzzleHttp\Handler\CurlHandler), Object(GuzzleHttp\Handler\EasyHandle), Object(GuzzleHttp\Handler\CurlFactory))\n#2 /var/www/html/guacamole-php-sdk/vendor/guzzlehttp/guzzle/src/Handler/CurlHandler.php(47): GuzzleHttp\Handler\CurlFactory::finish(Object(GuzzleHttp\Handler\CurlHandler), Object(GuzzleHttp\Handler\EasyHandle), Object(GuzzleHttp\Handler\CurlFactory))\n#3 /var/www/html/guacamole-php-sdk/vendor/guzzlehttp/guzzle/src/Handler/ in /var/www/html/guacamole-php-sdk/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php on line 211