@zhannak thank you for testing and looking into this!
1. The only plugin that has caching is Hummingbird Pro. I disabled it and tried again and it did not work.
2. I created a new, very simple form and now cannot get this new one to submit at all https://duthiepower.com/testing-form-page/ (FYI I am using Chrome, which seems to have the most problems)
3. I have the pro paid version. Should I still try to re-install an old version?
Thank you,