Efficient evolved packet system (EPS) fallback

A method performed by a session management system, the method comprising:

• receiving a rejection message that indicates a rejection to set up a call in a 5th Generation (5G) network by a 5G Radio Access Network (RAN);
• in response to receiving the rejection message, transmitting a request to establish a dedicated bearer through a 4th Generation (4G) network;
• and
• after a predetermined time of transmitting the request, transmitting an indication of a call failure to a policy control function (PCF) or a policy and charging rules function (PCRF).

A system comprising:

• at least one processor;
• and
• at least one memory storing instructions, the instructions being executable by the at least one processor to perform operations comprising:
• receiving a rejection message that indicates a rejection to set up a call in a 5th Generation (5G) network by a 5G Radio Access Network (RAN);
• in response to receiving the rejection message, transmitting a request to establish a dedicated bearer through a 4th Generation (4G) network;
• and
• after a predetermined time of transmitting the request, transmitting an indication of a call failure to a policy control function (PCF) or a policy and charging rules function (PCRF).