Your page has hidden technical errors running in the background. These can cause features to break unexpectedly for some visitors without any obvious sign that something went wrong.
On WordPress
Install the free Query Monitor plugin — it breaks down JavaScript errors by plugin so you can pinpoint the source without guessing. Also check Dashboard → Updates for plugins or themes with a pending update, as many JS errors are fixed in newer versions.
On Shopify
Go to Online Store → Themes → Actions → Edit code and check theme.liquid for broken script references. For app-related errors, go to the app's support page in the Shopify App Store — most app developers list known bugs and fixes there.
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