Wysija and calendar widget problem

Hi!
I’m using Polylang 1.2.4 to handle English and Italian in https://egle.is website, and I just installed Newsletters Wysija 2.5.9.2 plugin.

I found that if Wysija is active, Polylang does not translate correctly the calendar widget in the blog sidebar: months and weekdays are always in Italian (my WordPress installation is in Italian)
Disabling Wysija all works fine.

Here my settings:
– static homepage
– permalinks with just article names
– language set by content without url modification, eg: https://egle.is/the-blog/ (English) and https://egle.is/il-blog/ (Italian)

Thanks in advance!
-Erich

https://www.ads-software.com/plugins/polylang/