In some examples, an anchoring network system (e.g., PCSCF) of a telecommunications network can receive first data requesting a network service (e.g., eSRVCC) from a network terminal (e.g., UE). The anchoring system can determine that the network service is not supported in an access network to which the terminal is connected. The anchoring system can determine second data that does not request the predetermined network service, and transmit the second data to a core network system (e.g., SCSCF). In some examples, an application server can retrieve location information (e.g., LAC) of the terminal and determine that the service is not supported based on the location information. In some examples, an anchoring network system can remove a network-service system (e.g., ATCF or SCCAS) from a signaling chain associated with the terminal. In some examples, the terminal can determine whether SRVCC is supported based on an attach result.