Fatal Error / Conflict with WooCommerce MailerLite Plugin

Hi Support,

I’ve been trying to fix this issue with MailerLite, but at the end they said it’s an incompatibility with your plugin and theirs. When their plugin is activated, there is a fatal Error sending emails.

Here is the latest error when I active the WooCommerce MailerLite Plugin:

Fatal error: Uncaught Error: Call to undefined function GuzzleHttp\Psr7\uri_for()
in /home3/lk3tc001/public_html/wp-content/plugins/gmail-smtp/google-api-php-client/vendor/google/auth/src/OAuth2.php on line 1245

Call stack:

Google\A\OAuth2::coerceUri()
wp-content/plugins/gmail-smtp/google-api-php-client/vendor/google/auth/src/OAuth2.php:670

Google\A\OAuth2::setAuthorizationUri()
wp-content/plugins/gmail-smtp/google-api-php-client/vendor/google/auth/src/OAuth2.php:327

Google\A\OAuth2::__construct()
wp-content/plugins/gmail-smtp/google-api-php-client/src/Google/Client.php:942

Google_Client::createOAuth2Service()
wp-content/plugins/gmail-smtp/google-api-php-client/src/Google/Client.php:922

Google_Client::getOAuth2Service()
wp-content/plugins/gmail-smtp/google-api-php-client/src/Google/Client.php:274

Google_Client::fetchAccessTokenWithRefreshToken()
wp-content/plugins/gmail-smtp/google-api-php-client/src/Google/Client.php:255

Google_Client::refreshToken()
wp-content/plugins/gmail-smtp/class.phpmaileroauthgoogle.php:150

GmailXOAuth2::getOauth64()
wp-includes/PHPMailer/SMTP.php:597

PHPMailer\P\SMTP::authenticate()
wp-content/plugins/gmail-smtp/class.phpmaileroauth.php:150

PHPMailerOAuth::smtpConnect()
wp-includes/PHPMailer/PHPMailer.php:1944

PHPMailer\P\PHPMailer::smtpSend()
wp-includes/PHPMailer/PHPMailer.php:1637

PHPMailer\P\PHPMailer::postSend()
wp-includes/PHPMailer/PHPMailer.php:1470

PHPMailer\P\PHPMailer::send()
wp-content/plugins/gmail-smtp/main.php:949

gmail_smtp_pre_wp_mail()
wp-includes/class-wp-hook.php:292

WP_Hook::apply_filters()
wp-includes/plugin.php:212

apply_filters()
wp-includes/pluggable.php:211

wp_mail()
wp-content/plugins/gmail-smtp/main.php:186

GMAIL_SMTP::test_email_settings()
wp-content/plugins/gmail-smtp/main.php:123

GMAIL_SMTP::options_page()
wp-includes/class-wp-hook.php:292

WP_Hook::apply_filters()
wp-includes/class-wp-hook.php:316

WP_Hook::do_action()
wp-includes/plugin.php:484

do_action()
wp-admin/admin.php:259

require_once()
wp-admin/options-general.php:10

Thank you.