In some cases, digital products may incur shipping fees at checkout.
This issue can occur even when the product weight is set to 0kg. When this happens, there is a high possibility that the package weight has been added to the order, giving it a weight of over 0kg.
Additionally, ensure that the "This is a physical product" option is left unchecked in the Shopify product settings for the product to be recognized as a digital product.
By removing the check from this option, the product will not display shipping rates and will be recognized as a digital product.
Once this setting is configured, the shipping method will be excluded during checkout.