diff --git a/components/rest-sendgrid/src/org/aplex/rest_sendgrid/core.cljc b/components/rest-sendgrid/src/org/aplex/rest_sendgrid/core.cljc
index 9b1e46f..31c19c2 100644
--- a/components/rest-sendgrid/src/org/aplex/rest_sendgrid/core.cljc
+++ b/components/rest-sendgrid/src/org/aplex/rest_sendgrid/core.cljc
@@ -7,8 +7,9 @@
 (def api-config (atom {:api-host "https://api.sendgrid.com/"
                        :api-key (h/get-env "SENDGRID_API_KEY" "NO API KEY SUPPLIED")}))
 
-(def default-authed-payload {:headers {"Authorization" (str "Bearer " (:api-key @api-config))
-                                       "content-type" "application/json"}})
+(defn default-authed-payload []
+  {:headers {"Authorization" (str "Bearer " (:api-key @api-config))
+             "content-type" "application/json"}})
 
 (defn init-config [cfg]
   (reset! api-config (merge @api-config cfg)))
@@ -19,7 +20,7 @@
 (defn send-email
   "https://docs.sendgrid.com/api-reference/mail-send/mail-send"
   [email]
-  (merge default-authed-payload
+  (merge (default-authed-payload)
          {:uri (build-url "/mail/send")
           :method :post
           :format (json-request-format)