fix(accounts): convert default dunning fee to invoice currency

(cherry picked from commit 4235134a95)

# Conflicts:
#	erpnext/accounts/doctype/dunning/dunning.json
#	erpnext/accounts/doctype/sales_invoice/mapper.py

erpnext/accounts/doctype/dunning/dunning.js

@@ -161,8 +161,16 @@ frappe.ui.form.on("Dunning", {
 	company_address: function (frm) {
 		erpnext.utils.get_address_display(frm, "company_address");
 	},
-	dunning_type: function (frm) {
-		frm.trigger("get_dunning_letter_text");
+	dunning_type: async function (frm) {
+		if (frm.doc.dunning_type && flt(frm.doc.conversion_rate) > 0) {
+			const { message } = await frappe.db.get_value(
+				"Dunning Type",
+				frm.doc.dunning_type,
+				"dunning_fee"
+			);
+			await frm.set_value("dunning_fee", flt(message.dunning_fee) / frm.doc.conversion_rate);
+		}
+		return frm.trigger("get_dunning_letter_text");
 	},
 	language: function (frm) {
 		frm.trigger("get_dunning_letter_text");

erpnext/accounts/doctype/dunning/dunning.json

@@ -114,8 +114,6 @@
   },
   {
    "default": "0",
-   "fetch_from": "dunning_type.dunning_fee",
-   "fetch_if_empty": 1,
    "fieldname": "dunning_fee",
    "fieldtype": "Currency",
    "label": "Dunning Fee",
@@ -399,7 +397,7 @@
  ],
  "is_submittable": 1,
  "links": [],
- "modified": "2026-05-30 20:40:30.851842",
+ "modified": "2026-10-22 11:30:44.883211",
  "modified_by": "Administrator",
  "module": "Accounts",
  "name": "Dunning",

erpnext/accounts/doctype/sales_invoice/sales_invoice.py

@@ -3017,7 +3017,7 @@ def create_dunning(source_name, target_doc=None, ignore_permissions=False):
 			dunning_type = frappe.get_doc("Dunning Type", dunning_type)
 			target.dunning_type = dunning_type.name
 			target.rate_of_interest = dunning_type.rate_of_interest
-			target.dunning_fee = dunning_type.dunning_fee
+			target.dunning_fee = flt(dunning_type.dunning_fee) / target.conversion_rate
 			target.income_account = dunning_type.income_account
 			target.cost_center = dunning_type.cost_center
 			target.language = source.language