There are several reasons that the add to cart step may not be working. The solution to the issue will depend on the platform you are using Sign Customiser with.
Shopify
Too Many Variants
If you are not subscribed to the Shopify Plus plan you can add up to 1,000 new variants in a day before the limit is reached. When you reach this limit, Sign Customiser will not be able to create the custom sign product in your store. To resolve this, upgrade to Shopify Plus.
Incomplete Location Fulfilment
If your store uses Shopify Locations to manage inventory your default location must have fulfilment enabled, otherwise when someone tries to create a custom sign and add it to their cart it will show as "out of stock" and produce an error.
To enable fulfilment for your default location:
Log into your Shopify admin
Click on "Settings" in the bottom left corner of the sidebar
Click on "Locations"
Click on your default location
If you only have a single location, click on that one
If you have multiple locations, look for the name of the location in the card that says "Default location", then click on that location in the "All locations" card
In the "Fulfilment" card check to see if "Shipping" is enabled
If it says "off", click on it
Scroll down to the card that says "Fulfillment locations" and click "Add locations"
Select your default location in the window that appears then click "Add"
WordPress/WooCommerce/Custom
If there are issues adding to cart with WordPress/WooCommerce/Custom integrations it is likely a communication issue between Sign Customiser and your website.
To find out what error is occurring we can look at the logs of the integration within Sign Customiser:
Log into your Sign Customiser account
From the homepage, click on "Tools"
Click on "Integrations"
Click on your integration
This page will contain logs of any requests made to your website. Look for any red status codes that start with a 4 or a 5 like
500
or400
or422
If you see requests with these status codes it indicates an error from your server when we tried creating the product. You can click on the logs and see the detailed error to help you debug within your specific platform