“no images assigned to this gallery” when switching to english

Hello,

I’ve a site with two different languages (french & english) with the Border theme. It had been working well for a few months.
Now, from few days (and I didn’t perform any direct action on the site, except updates on wordpress extensions) when I switch from french to english (I’ve set Polylang for multi-language), this message is displayed in place of any gallery :
“Currently there are no images assigned to this gallery”
This is working fine when the language is french. I cannot understand why there is now this message.

The menu item that leads to the gallery is a personalized link like this, in order to have all frames in english (title, menus…) : “https://pascalechevest.com/?border_gallery=distances&lang=en”

My permalink setting is “simple”.
The front page is static with a gallery for displaying photos.
I’ve disabled one by one all wordpress extensions, but this doesn’t solve the language issue.
I’ve contacted the theme author, but he is saying that this is a Polylang issue.
I’m using the latest Polylang version (2.8.3) with WordPress version 5.5.1

Do you have any clue, please, for solving this issue ?

Thanks
Pascal

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