I got a hint via private message.
The problem i had was something with the website of wunderlist.
I deleted all cookies and the cache.
Following i need to generate a new access token.
Now its working.

Special thanks to SexyTrogg.

Hey guys,

i have the following problem:

• header will be shown
• list is empty
• The code in line 42 always returns “undefined”

it looks to be the same problem Kukielka58 had.
Did someone find out where the problem could be?

if i use:
curl -H “X-Access-Token: TOKEN” -H “X-Client-ID: ID” https://a.wunderlist.com/api/v1/lists

the console returns: “{“unauthorized”: true}” but i have no idea why.

this are my configs:

i hope someone can help me.

With best regards.
Headcrush