If you are using the "Breeze" Plugin by Cloudways, you may encounter some issues with empty carts when visiting the checkout page. This is due to aggressive page caching (which is a good thing!), but it can be easily resolved by requesting that WP Engine set up a special cache exception for your checkout page.
You need to exclude checkout pages by following these instructions:
Step 1: Note down the slug of your checkout page from the general settings
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Step 2: Open the settings of "Breeze" under the Settings tab.
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Step 3: Jump on the "Advanced Options" tab.
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Step 4: Locate the option "Never Cache these URLs"
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Step 5: To exclude “checkouts” pages enter your noted checkout page slug (from step 1) as shown in screenshot-
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Step 6: Click on the Save Changes button to save the settings.
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By default, the Checkout page's slug is "checkouts". If you had changed the checkout pages slug for any reason get the slug from FunnelKit (formerly WooFunnels) > Settings > General > Permalinks.