Now I see, here is the diagnostic test.
Mailer: postsmtp
HostName: ahabahairspa.com
cURL Version: 7.47.0
OpenSSL Version: OpenSSL/1.0.2g
OS: Linux smooth-sunset 4.9.58-xxxx-std-ipv6-64 #1 SMP Mon Oct 23 11:35:59 CEST 2017 x86_64
PHP: Linux 7.4.5 en_US.UTF-8
PHP Dependencies: iconv=Yes, spl_autoload=Yes, openssl=Yes, sockets=Yes, allow_url_fopen=Yes, mcrypt=No, zlib_encode=Yes
WordPress: 5.6.1 en_US UTF-8
WordPress Theme: Haircut
WordPress Plugins: AAAA Service, AAAA Shortcodes, Akismet Anti-Spam, Better Search Replace, Better WordPress Minify, Social Gallery and Widget, Classic Editor, GDPR Cookie Consent, Smash Balloon Custom Facebook Feed, Duplicator, Enable jQuery Migrate Helper, Google Analytics Dashboard for WP (GADWP), Smash Balloon Instagram Feed, WPZOOM Instagram Widget, Jetpack by WordPress.com, WpDevArt Social Like Box, Limit Login Attempts, Facebook for WordPress, PHP Compatibility Checker, Post SMTP, WordPress Importer, Yoast SEO, WP Instagram Widget, Clef, WPForms Lite
WordPress wp_mail Owner: /home/forge/ahabahairspa.com/public/wp-content/plugins/post-smtp/Postman/PostmanWpMailBinder.php
WordPress wp_mail Filter(s): wp_staticize_emoji_for_email, PostsmtpMailer->get_mail_args
WordPress phpmailer_init Action(s): PostsmtpMailer->phpmailer_smtp_init
Postman: 2.0.21
Postman Sender Domain (Envelope|Message): ahabahairspa.com | ahabahairspa.com
Postman Prevent Message Sender Override (Email|Name): Yes | Yes
Postman Active Transport: SMTP (smtp:tls:oauth2://smtp.gmail.com:587)
Postman Active Transport Status (Ready|Connected): Yes | Yes
Postman Deliveries (Success|Fail): 11 | 0
Postman Email Log (Enabled|Limit|Transcript Size): Yes | 250 | 250