I've just started working on updating an old website for a company. One of their concerns is that they've not sold anything from their online store. I tried to buy something on their website to test it, and it seems that it's impossible to actually complete a checkout, since the final step, selecting a payment option, just tries to load forever.
Here's a picture to show you exactly what I mean.
For an eCommerce website, this is obviously a huge problem. I've looked for what could be causing it, however since I didn't build the website or set up this plugin originally, I'm not even sure what it could be.
I haven't updated to the latest version of Woocommerce, as it's not compatible with the custom theme. Could that be causing it? Any help is appreciated!