I couldn’t reopen the topic so I am writing it again (I have already contacted with the plugin developers and gave me a workaround but I want also to check with you in case you have moved the options to some other place. They told to go on page “Payments”, go to “Payment options” and select “Switch to classic payment”. Since there is no such page I have looked on Cart, Checkout and Account pages but I cannot find such option. So, is it something that has changed on theme installing?).
I know I have marked it as solved but after I checked with the WooCommerce forum the problem of not finding the button is on the page builder I am using which is WpBakery which is bundled with the theme. Since, the builder is bundled and have not purchased it from them, they cannot offer support. I have also installed Gutenberg in order to switch to it and find the setting according to WooCommerce but is not working. I am switching to Gutenberg but for some reason the page reloads on WpBakery.