Error when translating elements of post comments

Hello, I’m using THinkUpThemes – Consulting themes. I’m working on a two-language version of the site (Polish and English) and for that I used PolyLang plugin. All elements were translated except for the “Leave a comment” section and the “Send a message” button. (screen in the link below). These are elements of the Blog. I’ve written to the support from the theme but they didn’t help, they refer to the plug-in creators. So my question is, do you have any idea how to translate these two sections? Is there any way for PolyLang to read these elements as text strings?

Screen shot: https://i.imgur.com/UZWB3eq.png

The page I need help with: [log in to see the link]