PHP Fatal error: Uncaught Error: Cannot access private property

Hi,
I get an http error 500 when I submit an Elementor form. The form is submitted and the mail is sent, but the end-user get the message “error”.
When I check the logs, it seems that Post SMTP is faulty:

*19957 FastCGI sent in stderr: "PHP message: PHP Fatal error:  Uncaught Error: Cannot access private property WP_Statuses_Core_Status::$_builtin in /emploi.anne-sophie-pic.com/wp-includes/post.php:2058
Stack trace:
#0 /emploi.anne-sophie-pic.com/wp-includes/link-template.php(129): is_post_status_viewable()
#1 /emploi.anne-sophie-pic.com/wp-includes/link-template.php(332): wp_force_plain_post_permalink()
#2 /emploi.anne-sophie-pic.com/wp-includes/link-template.php(201): get_post_permalink()
#3 /emploi.anne-sophie-pic.com/wp-includes/post.php(4229): get_permalink()
#4 /emploi.anne-sophie-pic.com/wp-content/plugins/post-smtp/Postman/Postman-Email-Log/PostmanEmailLogService.php(163): wp_insert_post()
#5 /emploi.anne-sophie-pic.com/wp-content/plugins/post-smtp/Postman/Postman-Email-Log/PostmanEmailLogService.php(108): PostmanEmailLogService->writeToEmailLog()
#6 /emploi.anne-sophie-pic.com/wp-content/plugins/post-smtp/Postman/Postman-Email-Log/Pos" while reading response header from upstream

Everything is up-to-date, and I can’t figure out the issue.
Thanks for your help.

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