A method for a system comprising a 5G Fixed Mobile Interworking Function Database entity, FMIF-DB, adapted for interacting with a Wireline 5G Access Network, W-5GAN, connecting to a Fixed Network Residential Gateway, FN-RG,, the W-5GAN comprising a Wireline Access Node, AN, and a 5G Fixed Mobile Interworking Function, FMIF,, the FMIF connecting to Access and Mobility Management Function, AMF and to a User Plane Function, UPF, and the FMIF-DB, the wireline Access Node, coupling to a Fixed Network Residential Gateway, a FN-RG providing services such as TV, Internet and voice, the FMIF-DB moreover coupling to a provisioning service entity, the FMIF-DB, being configured to hold - User entity, UE, credentials for providing an identity of the FN-RG as a User Entity, UE indexed by a circuit ID, and - UE configuration data for the FN-RG, the method comprising the FMIF-DB - receiving a request to setup UE credential and configuration data for the FN-RG identified by the circuit identity of the FN-RG, from the provisioning service node, - creating an entry for the FN-RG, the method further comprising the FMIF-DB engaging in a call flow for the FN-RG, the FMIF-DB - receiving a request message including the circuit identity, ID, from the 5G Fixed Mobile Interworking Function Database entity, FMIF,, - transmitting a response message to the FMIF for mapping the circuit ID with a set of UE parameters, - allowing for the FMIF to interact with the AMF to engage in NAS procedures (85, 86, 87), - receiving a store request message for updating the FMIF-DB with dynamic data from a FMIF, - transmitting a response to the FMIF. the FMIF-DB, being configured to hold - User entity, UE, credentials for providing an identity of the FN-RG as a User Entity, UE indexed by a circuit ID, and - UE configuration data for the FN-RG, - User entity, UE, credentials for providing an identity of the FN-RG as a User Entity, UE indexed by a circuit ID, and - UE configuration data for the FN-RG, the method comprising the FMIF-DB - receiving a request to setup UE credential and configuration data for the FN-RG identified by the circuit identity of the FN-RG, from the provisioning service node, - creating an entry for the FN-RG, - receiving a request to setup UE credential and configuration data for the FN-RG identified by the circuit identity of the FN-RG, from the provisioning service node, - creating an entry for the FN-RG, the method further comprising the FMIF-DB engaging in a call flow for the FN-RG, the FMIF-DB - receiving a request message including the circuit identity, ID, from the 5G Fixed Mobile Interworking Function Database entity, FMIF,, - transmitting a response message to the FMIF for mapping the circuit ID with a set of UE parameters, - allowing for the FMIF to interact with the AMF to engage in NAS procedures (85, 86, 87), - receiving a store request message for updating the FMIF-DB with dynamic data from a FMIF, - transmitting a response to the FMIF. - receiving a request message including the circuit identity, ID, from the 5G Fixed Mobile Interworking Function Database entity, FMIF,, - transmitting a response message to the FMIF for mapping the circuit ID with a set of UE parameters, - allowing for the FMIF to interact with the AMF to engage in NAS procedures (85, 86, 87), - receiving a store request message for updating the FMIF-DB with dynamic data from a FMIF, - transmitting a response to the FMIF.