If you are using "Cachify" plugin, you may encounter some issues with Aero/the Funnel Builder Checkout page when visiting the checkout. This is due to aggressive page caching (which is a good thing!), but it can be easily resolved by excluding the checkout page URI from cache plugin.
You need to exclude checkout pages by following these instructions-
Step 1: Note down the checkout page ID of your checkout page from here.
Step 2: Open the settings of “Cachify”
Step 3: Locate for setting "Cache Exception"
Step 4: To exclude "checkouts" pages enter your noted checkout page ID (from step 1) with special characters as shown in screenshot:
Step 5: Click on "Save all changes".
Note: By default, Checkout page's slug is "checkouts". If you had changed the checkout pages slug for any reason get the slug from Global Settings > Miscellaneous tab > Checkout Page Slug