Delivery charge problem

please help me
for one product we have 10 delivery charge
if a customer add more than one products in cart it should show only 10 delivery charge
previously it was like that but now every time one products added plus 10 and plus 10

Not quiet sure I understand you question, but if you check the shipping tab for the product (as opposed to the shipping method) you will likely find that 10 is set as the shipping charge, that is charged for each quantity purchased (but it is odd that it was working ok for you previously).

please any one help me how to put only one delivery charge for one user at a time

can you please help me how to put only one delivery charge for one user at a time

Do you use Multi-Vendor? Are these products from different vendors?

yes we use multivendor for both conditions we charge one delivery charge for one user at atime because we deliver the all vendors products

If the issue is as I described in the earlier post remove that charge (on the shipping tab of the product) Then you create a new shipping method. Do this by opening the admin panel and then go to the menu path administration/shipping & taxes/shipping methods.

See the documentation for more detail.

Please pay attention to the following module

https://docs.cs-cart.com/latest/user_guide/addons/fulfillment/index.html