How to find an issue on OpenCart?

Question

opencart

The site worked fine, but I installed a lot of plugins and checked them after installation, that is, they worked fine (15 pieces)
After installation, I did not check how other parts of the site react to this plugin.
I’m looking now that there is a problem when placing an order and does not allow to place an order.
Please tell me how to find the problem without deleting all the plugins that I installed.
Site riess.ru

Answer 1

You can look at the error log of OpenCart or php, maybe it will help.