diff --git a/calls.go b/calls.go
index c884f5c..30a6e42 100644
--- a/calls.go
+++ b/calls.go
@@ -90,9 +90,9 @@ type CallCreateParams struct {
 
 // Stores response for making a call.
 type CallCreateResponse struct {
-	Message     string      `json:"message" url:"message"`
-	ApiID       string      `json:"api_id" url:"api_id"`
-	RequestUUID interface{} `json:"request_uuid" url:"request_uuid"`
+	Message     string `json:"message" url:"message"`
+	ApiID       string `json:"api_id" url:"api_id"`
+	RequestUUID string `json:"request_uuid" url:"request_uuid"`
 }
 
 type CallListParams struct {