Email invite disappeared after clicking on "Accept" now nowhere to be found

Just got an invite for a job interview. At the top of the message "Accept", "Decline" etc could be seen, next to the calendar icon.

Clicked on "Accept". Email disappeared. Nothing on my calendar.

It was moved to the Trash, same prompt at the top. Instead of manually creating the entry, clicked on Accept. Email disappeared from trash. Nothing on my calendar. Checked all folders on Mail app. Checked email web client. No trace of the invite whatsoever.

Clicking on "Mailbox" then "Reconstruct" does nothing. No emails to recover. Any ideas? Writing back to potential employer and painting myself as too stupid to operate a basic email client is something I would like to avoid, despite knowing there's dozens of users that have reported this (as shown on other entries here).