registration of iRigHD2 impossible

[meder]

Hi!
I own an iRigHD2 and want to use it with my iPhone7+
The problem are:
1) I cannot register my device because the Serialnumber is not accepted.
2) If I plug in my guitar, the device receives signals (LED-colour changes) but I cannot hear any sound on my headphone, means, there is no output.
Exists an user-manual for the amplitude-app in German? The functions are not as intuitive as I need.
Thanks!
Unfortunately the IK-Servic doesn't answer me

[Peter_IK]

Hi, please note that you need to register IK hardware at http://www.ikmultimedia.com/registration (some people try to use Authorization Manager which is for software).

There is no German manual at this time.

IK Support typically answers tickets within one business day. What is your ticket number?