Custom 404error page trashed

Hello,
Sorry to post again as I saw 2 different posts posted by 2 other users about this subject but the answer and the solution was not posted.
Regularly, every day or often, the personalized page error 404 I created was moved to the trash… Only the main page (in French), not the translated in English.
My configuration :
– WordPress last version
– Theme Pen (free version)
– 404page plugin (work perfectly even this)
– redirection plugin
– yoast plugin
– polylang plugin
And since yesterday to get more information about this trouble :
– WP Activity Log
I get too an Sandbox version of this site on a subdomain to try and test, sorry a staging version.
The default error page was the French version, the English version work too perfectly, was never moved on the trash and appear when you are on the English version of the site or from an english speaking brother. When the French version was on the trash, the English version didn’t load, only the default error boring page.
This morning I get this message (read on the log of WP Activity Log) :

24/06 10:14:16.088 - ID2012- System - (IP) - Deleted - Moved to the trash ID736, Type: Page, statuts published

I wasn’t logged on the backoffice of the site.
I read the log of the plugin redirection and I found : nothing detected at this time.
So maybe a maintenance cron made it but I didn’t found it…
I will update this post if I found an issue or if I get more information.
Sorry for my English as I’m French
Thank you for your help
Didier
PS : maybe the easter eggs I put on the error page disturb the susceptibility and the cinematic taste of the software ??
All plugins (configuration file), all up to date :

| - Ergonomie (BackOffice) :
| Duplicate Post (BackOffice) -> OK au 28/05/2020 
| Simple Page Ordening (BackOffice - Gestion Ordre Post) -> OK au 28/05/2020 
| Wicked Folder (BackOffice - Gestion Post)-> OK au 28/05/2020 
| Absolutely Glamorous Custom Admin (BackOffice - Custom Admin) -> OK au 21/06/2020 
| - Sécurité (BackOffice) :
| WordFence (BackOffice - Security: Firewall, Antivirus, BrutForce Attack) -> OK au 05/06/2020
| WPS Hide Login (BackOffice - Security - Change Login Address) -> OK au 05/06/2020
| WP Activity Log (BackOffice - Security - Log) -> OK au 23/06/2020
| Activity Log (BackOffice - Security - Log) -> OK au 23/06/2020
| - Cache & Optimisation :
| Autoptimize (BackOffice - JavaScript & CSS) -> OK au 28/05/2020
| Async Javascript(BackOffice - JavaScript) -> OK au 13/06/2020
| Cache Enabler (BackOffice) -> OK au 28/05/2020 
| AMP (BackOffice - AMP pour Phone) -> OK au 10/06/2020
| Cloudflare (BackOffice) -> OK au 13/06/2020
| - SEO :
| YOAST SEO (BackOffice - SEO) -> OK au 28/05/2020
| Site Kit by Google -> OK au 22/06/2020
| Redirection (BackOffice - Gestion liens) -> OK au 31/05/2020
| 404Page (BackOffice) -> OK au 11/06/2020
|  -SauvegardeSite (BackOffice) :
| Duplicator (BackOffice - Sauvegarde - Duplication) -> OK au 12/06/2020
| All-In-One (BackOffice - Sauvegarde - Duplication) -> OK au 17/06/2020
| BackWPup (BackOffice - Sauvegarde database) -> OK au 12/06/2020
| - Codage / Programmation :
| 	
| - Législation (Frontside) :
| EU Cookies Law (FrontSide - Affichage pop-up) -> OK au 28/05/2020 
| - Gestionnaire Contact Form (BackOffice) :
| Contact From 7 (BackOffice) -> OK au 28/05/2020 
| Flamingo (BackOffice - DataBase de Contact Form 7) -> OK au 31/05/2020
| - Gestion Images (BackOffice) :
| reSmush.it (BackOffice - Resize Picture) -> OK au 13/06/2020
| Phenix Media Rename (BackOffice - Rename Media) -> OK au 13/06/2020
| - Gestion de contenu (BackOffice) :
| TinyMCE Advanced (BackOffice - Edit HTML) -> OK au 31/05/2020
| - Animation (FrontSide) :
| WP Sticky sidebar (FrontSide - Scrolling) -> OK au 19/06/2020
| - Langue - Traduction (BackOffice / Frontside) :
| Polylang (FrontSide - Gestion Multilang -> OK au 28/05/2020 
| Lingotek (BackOffice - Traduction) -> Testé au 28/05/2020 - Abandonné
|  login: *** - PW: *** 
| - OpenStreetMap (BackOffice - Carte) : 
| OSM Plug-in -> OK au 10/06/2020
| Ultimate Maps by Supsystic  -> OK au 28/05/2020
| - ChatBots (FrontSide) :
| 
| - Chat (Frontside) :
| Chaty (FrontSide - Live Chat) -> OK au 31/05/2020
| - Social Media Share Bar (FrontSide) :
| AddToAny Share Buttons (FrontSide - Social Network) -> OK au 31/05/2020 
| - Social Media Timeline Share (Frontside) :
| Facebook Timeline Widget SDK (FrontSide - Social Network) -> OK au 14/06/2020

• This topic was modified 4 years, 9 months ago by garfiedo.
• This topic was modified 4 years, 9 months ago by garfiedo.
• This topic was modified 4 years, 9 months ago by garfiedo.
• This topic was modified 4 years, 9 months ago by Yui.

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