---
title: "Our own `addToCart` callback is ignored: the button at the end of the size advice still adds to cart"
description: For some shops, Faslet keeps an add-to-cart script in the shop's settings.
---
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# Our own \`addToCart\` callback is ignored: the button at the end of the size advice still adds to cart
## The question
- Our `window._faslet.addToCart` callback only selects the recommended size, but the button at the end of the size advice still adds the product to the cart.
## Applies to
- A shop with its own Faslet integration that defines `window._faslet.addToCart`; any shop platform except Shopify, Lightspeed, WooCommerce and InstantCommerce, where Faslet adds to the cart itself
## Answer
For some shops, Faslet keeps an add-to-cart script in the shop's settings. When it is there, the button at the end of the size advice runs that script instead of your own `window._faslet.addToCart`. You can't see or change it yourself: ask us, and we remove it, so your own callback is used from then on.
Rather have no button at the end at all? We can switch it off for your shop instead.
Good to know: your shop's Faslet settings apply to every site that uses the same shop ID, such as a staging site and your live shop. Once the script is gone, each of them runs its own `window._faslet.addToCart`, so make sure the live one does what you want too. A site that doesn't set `window._faslet.addToCart` no longer shows the button at the end.
Want the button to say something else, now that it does something else? See [changing the texts in the size advice](https://site.faslet.me/knowledge-base/change-widget-texts).
## Why it happens
- An add-to-cart script kept in the store's settings at Faslet takes precedence over the shop's own `window._faslet.addToCart`
## Is this your situation?
- Your own `window._faslet.addToCart` never runs when the button at the end of the size advice is clicked (for example, a line it writes to the browser console never shows), while the button still does something, such as adding to the cart: this article.
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