Mine works perfect too!
Please check the Kodi version that you are using.
Also Check the version of the IPTV Stalker Client.
Another great addition to your Fire Tv toolbox is the WOKUNG Remote Control App for Mobiles that let you sideload apps from your Mobile and also emulate a Mouse on the Fire TV. That will help you with Sideloaded Android Apps that require mouse support (Eg.: Spotify, @TV Belkin and others.)
Good Luck!