añadiendo dependecies

api/helpers/enviar-whatsapp.js

 const axios = require('axios');
 const querystring = require('querystring'); // Luego modificar envíos por POST 
+const util = require('util');  
 
 module.exports = {
 

package-lock.json

@@ -3900,6 +3900,11 @@
       "resolved": "https://registry.npmjs.org/is-function/-/is-function-1.0.1.tgz",
       "integrity": "sha1-Es+5i2W1fdPRk6MSH19uL0N2ArU="
     },
+    "is-generator-function": {
+      "version": "1.0.7",
+      "resolved": "https://registry.npmjs.org/is-generator-function/-/is-generator-function-1.0.7.tgz",
+      "integrity": "sha512-YZc5EwyO4f2kWCax7oegfuSr9mFz1ZvieNYBEjmukLxgXfBUbxAWGVF7GZf0zidYtoBl3WvC07YK0wT76a+Rtw=="
+    },
     "is-hex-prefixed": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/is-hex-prefixed/-/is-hex-prefixed-1.0.0.tgz",
@@ -10450,6 +10455,26 @@
       "resolved": "https://registry.npmjs.org/utf8/-/utf8-3.0.0.tgz",
       "integrity": "sha512-E8VjFIQ/TyQgp+TZfS6l8yp/xWppSAHzidGiRrqe4bK4XP9pTRyKFgGJpO3SN7zdX4DeomTrwaseCHovfpFcqQ=="
     },
+    "util": {
+      "version": "0.12.3",
+      "resolved": "https://registry.npmjs.org/util/-/util-0.12.3.tgz",
+      "integrity": "sha512-I8XkoQwE+fPQEhy9v012V+TSdH2kp9ts29i20TaaDUXsg7x/onePbhFJUExBfv/2ay1ZOp/Vsm3nDlmnFGSAog==",
+      "requires": {
+        "inherits": "^2.0.3",
+        "is-arguments": "^1.0.4",
+        "is-generator-function": "^1.0.7",
+        "is-typed-array": "^1.1.3",
+        "safe-buffer": "^5.1.2",
+        "which-typed-array": "^1.1.2"
+      },
+      "dependencies": {
+        "safe-buffer": {
+          "version": "5.2.1",
+          "resolved": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.2.1.tgz",
+          "integrity": "sha512-rp3So07KcdmmKbGvgaNxQSJr7bGVSVk5S9Eq1F+ppbRo70+YeaDxkw5Dd8NPN+GD6bjnYm2VuPuCXmpuYvmCXQ=="
+        }
+      }
+    },
     "util-deprecate": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/util-deprecate/-/util-deprecate-1.0.2.tgz",

package.json

@@ -19,6 +19,7 @@
     "sails-hook-grunt": "^4.0.0",
     "sails-hook-orm": "^2.1.1",
     "sails-hook-sockets": "^2.0.0",
+    "util": "^0.12.3",
     "web3": "^1.2.6"
   },
   "devDependencies": {