If you do not have any specific errors in the Kaufland back office, please check the value of the "id_shipping_group" attribute for your Channel.
Here is the Kaufland help page on this subject: Kaufland Seller University - Shipping Settings
Why this happens
If the product exists but the offer is missing, it is usually because Kaufland cannot calculate the delivery cost.
The "id_shipping_group": This ID links your product to a specific shipping rate defined in your settings.