diff --git a/.changeset/shaggy-needles-raise.md b/.changeset/shaggy-needles-raise.md
new file mode 100644
index 0000000000..85fb346a85
--- /dev/null
+++ b/.changeset/shaggy-needles-raise.md
@@ -0,0 +1,5 @@
+---
+"medusa-payment-manual": patch
+---
+
+fix(medusa-payment-manual): Add missing update method
diff --git a/packages/medusa-payment-manual/src/services/manual-payment.js b/packages/medusa-payment-manual/src/services/manual-payment.js
index 775721a278..9afc5797e7 100644
--- a/packages/medusa-payment-manual/src/services/manual-payment.js
+++ b/packages/medusa-payment-manual/src/services/manual-payment.js
@@ -52,6 +52,16 @@ class ManualPaymentService extends PaymentService {
     return sessionData.data
   }
 
+  /**
+   .
+   * @param {object} sessionData - payment session data.
+   * @param {object} update - payment session update data.
+   * @returns {object} existing data merged with update data
+   */
+  async updatePaymentData(sessionData, update) {
+    return { ...sessionData.data, ...update.data }
+  }
+
   async deletePayment() {
     return
   }