If you host your site on “SiteGround” and using “SG Optimzer” Plugin, you may encounter some issues with empty carts when visiting the offer page. This is due to aggressive page caching (which is a good thing!), but it can be easily resolved by requesting that WP Engine setup a special cache exception for your offer page.
You need to exclude offer pages by following these instructions-
Step 1: Note down the slug of your offer page from here
Step 2: Open the settings of “SG Optimizer”.
Step 3: Locate for the option “Excluding URLs” on left side.
Step 4: To exclude “offer” pages enter your noted offer page slug (from step 1) as shown in screenshot: offer/*
Step 5: Click on Exclude button to add this slug as a exclusion.
Step 6: Here is final output slug added of offer page to exclude from cache.
Note: By default, UpStroke pages slug is “offer”. If you had changed the offer pages slug for any reason get the slug from here UpStroke > Global Settings > Miscellaneous tab > Offer Post Type Slug