default or selected kernelversion does not have config value CONFIG_HISAX_NO_LLC.
Result is shown for kernelversion 6.9.9

Disable sending low layer compatibility

configname: CONFIG_HISAX_NO_LLC

Linux Kernel Configuration
└─>Device Drivers
└─>ISDN support
└─>Old ISDN4Linux (deprecated)
└─>Passive cards
└─>Disable sending low layer compatibility
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
If you have trouble with some ugly exchanges try to select this
option.