diff --git a/oauth3.core.js b/oauth3.core.js
index c305578..b0f3498 100644
--- a/oauth3.core.js
+++ b/oauth3.core.js
@@ -394,12 +394,14 @@
     var clientAgreeTos = opts.clientAgreeTos || opts.client_agree_tos;
     var clientUri = opts.clientUri || opts.client_uri || opts.clientUrl || opts.client_url;
     var args = directive[type];
+    var otpCode = opts.otp || opts.otpCode || opts.otp_code || opts.otpToken || opts.otp_token || undefined;
     var params = {
       "grant_type": grantType
     , "username": opts.username
-    , "password": opts.password || undefined
+    , "password": opts.password || otpCode || undefined
     , "totp": opts.totp || opts.totpToken || opts.totp_token || undefined
-    , "otp": opts.otp || opts.otpCode || opts.otp_code || opts.otpToken || opts.otp_token || undefined
+    , "otp": otpCode
+    , "otp_code": otpCode
     , "otp_uuid": opts.otpUuid || opts.otp_uuid || undefined
     , "user_agent": opts.userAgent || opts.useragent || opts.user_agent || undefined // AJ's Macbook
     , "jwk": (opts.rememberDevice || opts.remember_device) && opts.jwk || undefined