Error 0x80EE0060

Value: -2131885984 | 0x80EE0060 | 2163081312

What does it mean ?

RTC_E_SIP_OTHER_PARTY_JOIN_IN_PROGRESS  
Join operation is in progress for another party
Value: 96 | 0x0060 | 0b0000000001100000

Where does it come from ?

FACILITY_RTC_INTERFACE  
RTC - Real-time Communications
Value: 238 | 0x0EE | 0b11101110

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