Error 0x80F00006

Value: -2131755002 | 0x80F00006 | 2163212294

What does it mean ?

RTC_E_PINT_STATUS_REJECTED_NO_ANSWER  
No Answer
Value: 6 | 0x0006 | 0b0000000000000110

Where does it come from ?

FACILITY_PINT_STATUS_CODE  
PINT - PSTN/Internet Interworking (VoIP)
Value: 240 | 0x0F0 | 0b11110000

Other Errors for FACILITY_PINT_STATUS_CODE