I’m getting a fatal error message involving Gmail SMTP

Hi, When I updated to the most recent version of the Gmail SMTP plugin, I received this fatal-error message:

Fatal error: Call to undefined function GuzzleHttp\Handler\curl_reset() in /homename/databasename/public_html/wp-content/plugins/gmail-smtp/google-api-php-client/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php on line 78

I updated the plugin today, because the prior version of the plugin produced a different type of fatal-error message:

Fatal error: Uncaught exception ‘Google_Auth_Exception’ with message ‘Error refreshing the OAuth2 token, message: ‘{ “error” : “invalid_grant” }” in /home/databasename/public_html/wp-content/plugins/gmail-smtp/google-api-php-client/src/Google/Auth/OAuth2.php:363 Stack trace: #0 /home/databasename/public_html/wp-content/plugins/gmail-smtp/google-api-php-client/src/Google/Auth/OAuth2.php(278): Google_Auth_OAuth2->refreshTokenRequest(Array) #1 /home/databasename/public_html/wp-content/plugins/gmail-smtp/google-api-php-client/src/Google/Client.php(457): Google_Auth_OAuth2->refreshToken(‘1/YFutmVVQKdF2k…’) #2 /home/databasename/public_html/wp-content/plugins/gmail-smtp/class.phpmaileroauthgoogle.php(142): Google_Client->refreshToken(‘1/YFutmVVQKdF2k…’) #3 /home/databasename/public_html/wp-content/plugins/gmail-smtp/PHPMailer/class.smtp.php(471): GmailXOAuth2->getOauth64() #4 /home/databasename/public_html/wp-content/plugins/gmail-smtp/class.phpmaileroauth.php(153): SMTP->authenticate(”, ”, ‘XOAUTH2’, ”, ”, Object(GmailXOAuth2)) #5 /h in /home/databasename/public_html/wp-content/plugins/gmail-smtp/google-api-php-client/src/Google/Auth/OAuth2.php on line 363

I don’t know what these fatal-error messages mean. What do you recommend? Thanks!

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