PLACE ORDER button is missing from my website on the CHECKOUT page

I am working on a woocommerce website using the theme- twenty twenty.the issue I am facing is that whenever I use the website on any phone or mobile device- IOS, android, any phone- the PLACE ORDER button is missing.
also, the payment options square is totally greyed out.
every single thing works fine on my Desktop/PC. however, only on phone and mobile devices, the entire thing is missing and that is causing major lags in my order and reach.

i am unable to reach out or contact the theme developers, too. please help!