I found Magento 2.3, 2.4 have problem to update shipping cost when change shipping method. We use cart rule to calculate shipping fee base on order amount.
In the video, "Best Method" is free for any order, the other method need > $300 for free.
I observe the following when the product does not change in cart.
Looking forward any comments.
Thanks in advance,
Do one thing disable the module bsscommerce/custom-shipping-method and check if its cause the issue. If not then write an email to BSS about this that their module is causing shipping related issue.
Or you can make your own
It doesn't related to the third party module.
The same issue happens on Flat Rate, Table rate built in delivery method.
I will try to add custom shipping module.
thanks for advise.
This problem could be caused by the custom module on your website. You can disable two modules: the shipping module and one step checkout module and try out the default Magento features.
Hope this can help you! Let me know if you need further assistance.
If issue solved, Click Kudos & Accept as Solution.
Thanks for your comment.
I did disabled one step checkout to test and it have same problem too.
For shipping module, I tried to use flat rate & fix amount also have same problem too.
I think it may be magento core problem.