400 bad request Anchor Text form/action(post)

Shopify Discussion

Topic summary

A user encounters a 400 Bad Request error when attempting to add a product (Sia Long Checkered Teddy Coat) to the cart on a Shopify store. The error occurs when submitting a form via POST to https://wearmiathelabel.com/fr/cart/add.

Potential causes identified:

  • Product may be unavailable or out of stock in the French region (/fr)
  • Incorrect form action URL (should POST to /cart/add instead of /fr/cart/add)
  • Missing or incorrect product variant ID in the submission
  • JavaScript potentially modifying form data incorrectly before submission

Recommended troubleshooting steps:

  • Verify product availability in Shopify Admin > Products for the appropriate language/region
  • Inspect the add-to-cart form action URL for accuracy
  • Use browser Developer Console (F12 > Network Tab) to monitor the actual data being sent
  • Test form submission with JavaScript disabled to isolate potential scripting issues

The issue remains unresolved and requires further investigation of the form implementation.

Summarized with AI on November 1. AI used: claude-sonnet-4-5-20250929.
1

Hey, I have been looking for a solution to this error message for several days now. However, I am unable to solve this problem. Has anyone had this problem before or can anyone help me with this? I look forward to receiving a response.

Error URL Anchor Text Linked From

400 Bad Request https://wearmiathelabel.com/fr/cart/add form/action(post) https://wearmiathelabel.com/fr/products/sia-long-checkered-teddy-coat
2

A problem with the way the request is being submitted to Shopify’s cart system is typically indicated by the “400 Bad Request” error. Here’s how to diagnose and resolve it:

Potential Reasons & Solutions
Verify whether the item is available for purchase.
In the chosen region, the Sia Long Checkered Teddy Coat may not be available or be out of stock (/fr for French).
In the Shopify Admin > Products section, see if the product is available.
Make sure it is accessible in the appropriate language and area.
Make Sure the Add-to-Cart Form Action Is Correct
Data from Shopify’s Add to Cart form ought to be posted to /cart/add rather than /fr/cart/add.
Check the Product Variant ID.
Shopify needs more than simply the product URL; it also needs a variation ID.
In the event that JavaScript alters the form submission, it may be transmitting inaccurate data.
Check if JavaScript changes the form data before submission by opening the Developer Console (F12 > Network Tab), then test by turning off JavaScript and submitting the form manually.