Add To Cart Function Stopped Working & Theme has switched back to Classic mode on its own!!

After spending 10 hours setting up conversion tracking with Google Tag Manager. I proceeded to setup woocommerce on the site. The Stripe gateway wasn't working when I tried to enter any payment options (credit card). So it took me 2 hours to figure out I had to use a completely different plugin. Once I activated the plugin, the checkout feature actually started to work. But after 1 successful transaction, the add to cart feature actually stopped working all together. smh

another 5 hours of troubleshooting lead me back to my home page inside my WordPress directory where I noticed my entire backend Dashboard>Pages>Home has diverted back to the "Classic" editor. I don't know why and how this has happened. Can I get some help, please?