diff --git a/pkg/checkout/mutation_payment_started.go b/pkg/checkout/mutation_payment_started.go
index 2829689..4f983e9 100644
--- a/pkg/checkout/mutation_payment_started.go
+++ b/pkg/checkout/mutation_payment_started.go
@@ -35,6 +35,11 @@ func HandlePaymentStarted(g *CheckoutGrain, m *messages.PaymentStarted) error {
 
 	payment, found := g.FindPayment(paymentID)
 
+	var sessionData *json.RawMessage
+	if m.SessionData != nil {
+		sessionData = (*json.RawMessage)(&m.SessionData.Value)
+	}
+
 	if found {
 		if payment.Status != "pending" {
 			return fmt.Errorf("PaymentStarted: payment already started")
@@ -54,7 +59,7 @@ func HandlePaymentStarted(g *CheckoutGrain, m *messages.PaymentStarted) error {
 			payment.Method = method
 		}
 		if m.SessionData != nil {
-			payment.SessionData = (*json.RawMessage)(&m.SessionData.Value)
+			payment.SessionData = sessionData
 		}
 		payment.StartedAt = &startedAt
 
@@ -64,7 +69,7 @@ func HandlePaymentStarted(g *CheckoutGrain, m *messages.PaymentStarted) error {
 			PaymentId:   paymentID,
 			Status:      "pending",
 			Amount:      m.Amount,
-			SessionData: (*json.RawMessage)(&m.SessionData.Value),
+			SessionData: sessionData,
 			Currency:    currency,
 			Provider:    provider,
 			Method:      method,