Polylang problem with Uncode theme

I’m testing polylang with Uncode theme. Everything is working well… (pages, posts, content blocks etc), exept the media. After I create the second language for a media, when I click save, a new media record is created with default flag and the plus sign and a new language with a numeric name in Polylang languages.

If I deactivate the Uncode theme, everything is working well with media translation.

I will appreciate your advice. Thank you very much.