diff --git a/src/orders/views/OrderReturn/utils.tsx b/src/orders/views/OrderReturn/utils.tsx
index 4ec0ac001..9d52be50d 100644
--- a/src/orders/views/OrderReturn/utils.tsx
+++ b/src/orders/views/OrderReturn/utils.tsx
@@ -56,12 +56,12 @@ class ReturnFormDataParser {
       ? this.formData.amount
       : undefined;
 
-  private getParsedLineData = function<
+  private getParsedLineData = <
     T extends OrderReturnFulfillmentLineInput | OrderReturnLineInput
   >(
     itemsQuantities: FormsetQuantityData,
     idKey: "fulfillmentLineId" | "orderLineId",
-  ): T[] {
+  ): T[] => {
     const { itemsToBeReplaced } = this.formData;
 
     return itemsQuantities.reduce((result, { value: quantity, id }) => {
diff --git a/tsconfig.json b/tsconfig.json
index 4b11a1952..c29037867 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -9,6 +9,7 @@
     "target": "es5",
     "noUnusedLocals": true,
     "noUnusedParameters": true,
+    "noImplicitThis": true,
     "paths": {
       "@assets/*": ["assets/*"],
       "@locale/*": ["locale/*"],