Fatal error

Hi there. Hitting the button to Authorize the Google Api details the page went blank with the following texts and more. Since then the front end only works till the shopping cart and the backend not at all. Please help.

: Fatal error: Uncaught GuzzleHttp\Exception\ConnectException: cURL error 6: Could not resolve host: oauth2.googleapis.com (see https://curl.haxx.se/libcurl/c/libcurl-errors.html) in /home/fiets.pe/public_html/wp-content/plugins/yaysmtp/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php:200 Stack trace: #0 /home/fiets.pe/public_html/wp-content/plugins/yaysmtp/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php(155): GuzzleHttp\Handler\CurlFactory::createRejection() #1 /home/fiets.pe/public_html/wp-content/plugins/yaysmtp/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php(105): GuzzleHttp\Handler\CurlFactory::finishError() #2 /home/fiets.pe/public_html/wp-content/plugins/yaysmtp/vendor/guzzlehttp/guzzle/src/Handler/CurlHandler.php(43): GuzzleHttp\Handler\CurlFactory::finish() #3 /home/fiets.pe/public_html/wp-content/plugins/yaysmtp/vendor/guzzlehttp/guzzle/src/Handler/Proxy.php(28): GuzzleHttp\Handler\CurlHandler->__invoke() #4 /home/fiets.pe/public_html/wp-content/plugins/yaysmtp/vendor/guzzlehttp/guzzle/src/Handler/Proxy.php(51): GuzzleHttp\Handler\Proxy::GuzzleHttp\Handler\{closure}() #5 /home/fiets.pe/public_html/wp-content/plugins/yaysmtp/vendor/guzzlehttp/guzzle/src/PrepareBodyMiddleware.php(66): GuzzleHttp\Handler\Proxy::GuzzleHttp\Handler\{closure}() #6 /home/fiets.pe/public_html/wp-content/plugins/yaysmtp/vendor/guzzlehttp/guzzle/src/Middleware.php(29):

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