Method and system to improve IMS registration failure due to P-CSCF server connection failure

A computer system, comprising:

• one or more processors;
• and
• a memory having instructions stored thereon, which when executed by the one or more processors cause the processors to perform:
• initiating a voice call, wherein the voice call comprises a voice session over 5G new radio (NR) initiated via a user equipment (UE);
• in response to a failure of a first connection to an initial Proxy-Call Session Control Function (P-CSCF) server, selecting a secondary P-CSCF server from a plurality of P-CSCF servers based on a round-robin scheme, wherein each of the plurality of P-CSCF servers are available to connect to the UE;
• and
• attempting to establish a second connection to the selected secondary P-CSCF server, wherein the secondary connection supports a registration to an IP Multimedia Subsystem (IMS) for the UE to conduct the voice call as the voice session over 5G NR;
• wherein the one or more processors are further configured to perform:
• in response to a failure of the UE to connect to all of the plurality of P-CSCF servers, disconnecting a Protocol Data Unit (PDU) session associated with the registration to the IMS for the UE;
• and
• performing a subsequent PDU session establish procedure for reconnecting the PDU session to restore P-CSCF addresses corresponding to the initial P-CSCF server and the plurality of P-CSCF servers.