Test mail shows Ajax error using Gmail SMTP server

Hiya,

I’m getting Ajax error upon sending a test mail using Google.

Disabled all other plugins
Ran connectivity test – showed all green
Restarted server

Any idea what could be wrong?

Thanks!

Here’s the diagnostics log:

Mailer: postsmtp
HostName: heroesinmarketing.com
cURL Version: 7.52.1
OpenSSL Version: OpenSSL/1.0.2u
OS: Linux 609554.cloudwaysapps.com 4.9.0-15-amd64 #1 SMP Debian 4.9.258-1 (2021-03-08) x86_64
PHP: Linux 8.0.15 C
PHP Dependencies: iconv=Yes, spl_autoload=Yes, openssl=Yes, sockets=Yes, allow_url_fopen=Yes, mcrypt=No, zlib_encode=Yes
WordPress: 5.9.2 nl_NL UTF-8
WordPress Theme: Built on Success
WordPress Plugins: Post SMTP, Really Simple SSL
WordPress wp_mail Owner: /home/609554.cloudwaysapps.com/fdzedfewcr/public_html/wp-content/plugins/post-smtp/Postman/PostmanWpMailBinder.php
WordPress wp_mail Filter(s): wp_staticize_emoji_for_email, PostsmtpMailer->get_mail_args
Postman: 2.0.24
Postman Sender Domain (Envelope|Message): stichtingheroesinmarketing.com | heroesinmarketing.com
Postman Prevent Message Sender Override (Email|Name): Yes | Yes
Postman Active Transport: Gmail API (https:login://www.googleapis.com:443)
Postman Active Transport Status (Ready|Connected): Yes | Yes
Postman Deliveries (Success|Fail): 0 | 36

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