A first base station, BS, (20, 102, 104) for handling a secondary cell group, SCG, failure, comprising: at least one storage device; and at least one processing circuit, coupled to the at least one storage device, wherein the at least one storage device stores, and the at least one processing circuit is configured to execute, instructions of: connecting to a communication device; transmitting a secondary node, SN, Addition Request message to a second BS (20, 102, 104) for the communication device; receiving a SN Addition Request Acknowledge message in response to the SN Addition Request message from the second BS (20, 102, 104), wherein the SN Addition Request Acknowledge message comprises a first plurality of configurations which configure the communication device to communicate with the second BS (20, 102, 104) and configure a data radio bearer, DRB, which is a SCG split bearer; transmitting a first message comprising the first plurality of configurations to the communication device, wherein the second BS (20, 102, 104) communicates with the communication device according to the first plurality of configurations; receiving a second message indicating the SCG failure from the communication device; and transmitting a third message configuring the DRB to be a master cell group, MCG, bearer or a MCG split bearer to the communication device. at least one storage device; and at least one processing circuit, coupled to the at least one storage device, wherein the at least one storage device stores, and the at least one processing circuit is configured to execute, instructions of: connecting to a communication device; transmitting a secondary node, SN, Addition Request message to a second BS (20, 102, 104) for the communication device; receiving a SN Addition Request Acknowledge message in response to the SN Addition Request message from the second BS (20, 102, 104), wherein the SN Addition Request Acknowledge message comprises a first plurality of configurations which configure the communication device to communicate with the second BS (20, 102, 104) and configure a data radio bearer, DRB, which is a SCG split bearer; transmitting a first message comprising the first plurality of configurations to the communication device, wherein the second BS (20, 102, 104) communicates with the communication device according to the first plurality of configurations; receiving a second message indicating the SCG failure from the communication device; and transmitting a third message configuring the DRB to be a master cell group, MCG, bearer or a MCG split bearer to the communication device. connecting to a communication device; transmitting a secondary node, SN, Addition Request message to a second BS (20, 102, 104) for the communication device; receiving a SN Addition Request Acknowledge message in response to the SN Addition Request message from the second BS (20, 102, 104), wherein the SN Addition Request Acknowledge message comprises a first plurality of configurations which configure the communication device to communicate with the second BS (20, 102, 104) and configure a data radio bearer, DRB, which is a SCG split bearer; transmitting a first message comprising the first plurality of configurations to the communication device, wherein the second BS (20, 102, 104) communicates with the communication device according to the first plurality of configurations; receiving a second message indicating the SCG failure from the communication device; and transmitting a third message configuring the DRB to be a master cell group, MCG, bearer or a MCG split bearer to the communication device.