Fred

Same problem, while using WordPress 5.x and block editor, all post categories are displayed, not filtered by language (related to the current post language).

Problem disapears if you activate “Classic Editor” plugin. So, is Polylang really compatible with WordPress 5.x and his blocks editor ?

[update]
All plugins disabled, added Email Log plugin in order to track sent e-mails, but issue remains : Payment accepted” orders and no e-mail sent. All other emails from the website are correctly sent.
No idea about where/what to look for in the plugin settings or code ?

It could be due to mutualized hosting: twitter has a maximum request number to its API per time and per IP address.
So, if many websites on the same server use the API with the same IP address, there will be no response after the request quota has been reached. And it seems to be very low (I’ve read about 1000/hour).

Perhaps duplicate but really not solved at all… (even using Social 2.7)

I still use Social 2.7, and there’s still the same problem.

Same problem, but it’s worse on my website, tweets aren’t downloaded, even if using manual forced download… no more tweets displayed for weeks

as reported here: https://www.ads-software.com/support/topic/twitter-tools-303-new-tweets-not-coming-in-for-3-weeks

You should have solved this problem, but for others who could get the same, just notice that the permalink is displayed when publishing your product (or post). A draft post has no permalink.
In order to check it without publishing it for anyone, set it as “private”.