Can’t Add More than 27 Fields; Switches Not Working

I’m editing the checkout form on [ redundant link removed ] and am running into two problems.

1. I currently have 26 fields under Additional Information. When I try adding more than that, they don’t save.

2. When I go to the General settings tab –> Switches, and under “Additional Fields Position on Checkout” try selecting any of the options other than the default (last option) and then saving, my choice doesn’t save.

I’m using the latest versions of Woocommerce and the Woocommerce Checkout Manager plugin. I’ve tried deactivating all other plugins and reverting to the Twenty Eighteen theme, but none of that worked.

Thanks,

The page I need help with: [log in to see the link]