QSM not sending email, not save results

Hi! I install a fresh plugin – QSM on site https://hiszpanskiprzykawie.pl and when i submit quiz. I see result page, but results not save and e-mail not send.
I turned off all other plugin and the same.
Look on test quiz: https://hiszpanskiprzykawie.pl/quiz/test-1/

For test also I tested QSM plugin and the same theme, different installation wordpress and plugin working. I don’t know why…

Quiz in different installation woredpress where working ok: https://test.wojaczek-kubica.eu/newspaper/quiz/test-1/

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