Remote Tvheadend access Kodi 17.1

Hello,

I have a problem. I used Tvheadend 4.1 and updated yesterday to 4.3 on a raspberry 3. Everything is working perfectly but have one problem. I can’t access it remotely from my android phone Kodi 17.1
I always get the error “access denied”

When I try it with iOS TvhClient, same user, same ext wlan no problem
Port 9981 is open or it wouldn’t work.

Any suggestions why it doesn’t work?
Specs:
Local: Raspberry 3, Tvheadend 4.3
Router tplink v900 port 9981 open

Extern:
Android 7 Huawei p9 lite Kodi 17.1 – not working
iOS 10.3.2 iPad Air 2 TvhClient- working

Thanks in advance