WordPress caught an error in Post SMTP

Hi guys,

Got a E_Error today and just wondering what the cause might be.

Error message was:

WordPress version 5.8
Current theme: Coach Network (version 0.1)
Current plugin: Post SMTP (version 2.0.23)
PHP version 7.3.29

Error Details
=============
An error of type E_ERROR was caused in line 329 of the file /home/neurolanguagecoa/public_html/neurolanguagecoachnetwork.com/wp-content/plugins/post-smtp/Postman/Postman-Mail/PostmanSmtpModuleTransport.php. Error message: Uncaught Error: Class 'PostmanAdminController' not found in /home/neurolanguagecoa/public_html/neurolanguagecoachnetwork.com/wp-content/plugins/post-smtp/Postman/Postman-Mail/PostmanSmtpModuleTransport.php:329
Stack trace:
#0 /home/neurolanguagecoa/public_html/neurolanguagecoachnetwork.com/wp-content/plugins/post-smtp/Postman/Postman-Mail/PostmanSmtpModuleTransport.php(294): PostmanSmtpModuleTransport->addSettings()
#1 /home/neurolanguagecoa/public_html/neurolanguagecoachnetwork.com/wp-includes/class-wp-hook.php(303): PostmanSmtpModuleTransport->on_admin_init('')
#2 /home/neurolanguagecoa/public_html/neurolanguagecoachnetwork.com/wp-includes/class-wp-hook.php(327): WP_Hook->apply_filters(NULL, Array)
#3 /home/neurolanguagecoa/public_html/neurolanguagecoachnetwork.com/wp-includes/plugin.php(470): WP_Hook->do_action(Array)
#4 /home/neurolanguagecoa/public_html/neurolanguagecoachnetwork.com/wp-admin/admin-ajax.php(45): do_action('admin_init')
#5 {main}
thrown

Diagnostics text is:

Mailer: postsmtp
HostName: neurolanguagecoachnetwork.com
cURL Version: 7.78.0
OpenSSL Version: OpenSSL/1.1.1k
OS: Linux vmi251363.contaboserver.net 3.10.0-1160.25.1.el7.x86_64 #1 SMP Wed Apr 28 21:49:45 UTC 2021 x86_64
PHP: Linux 7.3.29 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: 5.8 en_GB UTF-8
WordPress Theme: Coach Network
WordPress Plugins: Mobile Menu, 404page - your smart custom 404 error page, Add Admin CSS, Advanced Custom Fields PRO, WordPress Slider Plugin - Block Slider, Blocks Animation: CSS Animations for Gutenberg Blocks, Blocks CSS: CSS Editor for Gutenberg Blocks, CDN Enabler, The Events Calendar Countdown Addon, Display Environment Type, Elementor Pro, Elementor, Email Address Encoder ?, Enable Gzip Compression, The Events Calendar PRO, The Events Calendar Search Addon, GP Premium, Header Footer Code Manager, List category posts, Memberium, myCred, Post Duplicator, Post SMTP, Custom Query Blocks, Redirection, Redis Object Cache, Robots.txt Editor, Server IP & Memory Usage Display, Shortcode in Menus, ShortPixel Image Optimizer, Strong Testimonials, The Events Calendar Category Colors, The Events Calendar: Community Events, The Events Calendar, The Events Calendar Extension: Calendar Customizer, The Events Calendar Extension: Relabeler, Ultimate Addons for Gutenberg, Ultimate Member, Ultimate Member - Followers, Ultimate Member - Friends, Ultimate Member - Groups, Ultimate Member - Maps, Ultimate Member - Private Messages, Ultimate Member - myCRED, Ultimate Member - Notices, Ultimate Member - Real-time Notifications, Ultimate Member - Online, Ultimate Member - Profile Completeness, Ultimate Member - Profile tabs, Ultimate Member - reCAPTCHA, Ultimate Member - Social Activity, Ultimate Member - Social Login, Ultimate Member - Unsplash, Ultimate Member - User Notes, Ultimate Member - User Photos, Ultimate Member - User Tags, Ultimate Member - Yoast SEO, UpdraftPlus - Backup/Restore, URL Params, User Role Editor, USP Pro, Wordfence Security, Yoast SEO, Custom Body Class, WP HTML Mail - Email Template Designer, WP Rollback, WP Activity Log, WP STAGING PRO, Zapier for WordPress
WordPress wp_mail Owner: /home/neurolanguagecoa/public_html/neurolanguagecoachnetwork.com/wp-content/plugins/post-smtp/Postman/PostmanWpMailBinder.php
WordPress wp_mail Filter(s): wp_staticize_emoji_for_email, PostsmtpMailer->get_mail_args, Haet_Mail->style_mail
WordPress wp_mail_from Filter(s): wordfence::fixWPMailFromAddress
Postman: 2.0.23
Postman Sender Domain (Envelope|Message):  | efficientlanguagecoaching.com
Postman Prevent Message Sender Override (Email|Name): Yes | Yes
Postman Active Transport: Mailgun API (https://api.eu.mailgun.net:443)
Postman Active Transport Status (Ready|Connected): Yes | Yes
Postman Deliveries (Success|Fail): 339 | 0

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