diff --git a/components/authenticator.js b/components/authenticator.js
index 5a3a8d2..907eca8 100644
--- a/components/authenticator.js
+++ b/components/authenticator.js
@@ -10,7 +10,7 @@ module.exports.getAuth = function (username, password) {
         client_token: uuid(),
         uuid: uuid(),
         name: username,
-        user_properties: JSON.stringify({})
+        user_properties: '{}'
       }
 
       return resolve(user)
@@ -42,7 +42,7 @@ module.exports.getAuth = function (username, password) {
         uuid: body.selectedProfile.id,
         name: body.selectedProfile.name,
         selected_profile: body.selectedProfile,
-        user_properties: JSON.stringify(body.user.properties || {})
+        user_properties: parsePropts(body.user.properties)
       }
 
       resolve(userProfile)
@@ -92,7 +92,7 @@ module.exports.refreshAuth = function (accessToken, clientToken, selectedProfile
         client_token: uuid(),
         uuid: body.selectedProfile.id,
         name: body.selectedProfile.name,
-        user_properties: JSON.stringify(body.user.properties || {})
+        user_properties: parsePropts(body.user.properties)
       }
 
       resolve(userProfile)
@@ -141,3 +141,19 @@ module.exports.signOut = function (username, password) {
 module.exports.changeApiUrl = function (url) {
   api_url = url
 }
+
+function parsePropts (array) {
+  if (array) {
+    const newObj = {}
+    for (const entry of array) {
+      if (newObj[entry.name]) {
+        newObj[entry.name].push(entry.value)
+      } else {
+        newObj[entry.name] = [entry.value]
+      }
+    }
+    return JSON.stringify(newObj)
+  } else {
+    return '{}'
+  }
+}
diff --git a/package.json b/package.json
index 6f45508..e8a7dae 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "minecraft-launcher-core",
-  "version": "3.16.2",
+  "version": "3.16.3",
   "description": "Lightweight module that downloads and runs Minecraft using javascript / NodeJS",
   "main": "index.js",
   "dependencies": {