fix(medusa): removal of shipping methods on addOrUpdateLineItems (#4725)

* added removal of shipping methods on addOrUpdateLineItems

* Create lovely-beds-design.md

---------

Co-authored-by: Thijs Simons <thijs@careeraim.nl>
Co-authored-by: Oli Juhl <59018053+olivermrbl@users.noreply.github.com>

.changeset/lovely-beds-design.md

@@ -0,0 +1,5 @@
+---
+"@medusajs/medusa": patch
+---
+
+fix(medusa): removal of shipping methods on addOrUpdateLineItems

packages/medusa/src/services/cart.ts

@@ -765,7 +765,10 @@ class CartService extends TransactionBaseService {
 
     return await this.atomicPhase_(
       async (transactionManager: EntityManager) => {
-        let cart = await this.retrieve(cartId, { select })
+        let cart = await this.retrieve(cartId, { 
+          select, 
+          relations: ["shipping_methods"] 
+        })
 
         if (this.featureFlagRouter_.isFeatureEnabled("sales_channels")) {
           if (config.validateSalesChannels) {
@@ -900,6 +903,12 @@ class CartService extends TransactionBaseService {
             throw err
           })
 
+        if (cart.shipping_methods?.length) {
+          await this.shippingOptionService_
+            .withTransaction(transactionManager)
+            .deleteShippingMethods(cart.shipping_methods)
+        }
+
         cart = await this.retrieve(cart.id, {
           relations: [
             "items.variant.product.profiles",