A first base station, BS, 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 for the communication device ; receiving a SN Addition Request Acknowledge message in response to the SN Addition Request message from the second BS , wherein the SN Addition Request Acknowledge message comprises a first plurality of configurations which configure the communication device to communicate with the second BS 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 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 for the communication device ; receiving a SN Addition Request Acknowledge message in response to the SN Addition Request message from the second BS , wherein the SN Addition Request Acknowledge message comprises a first plurality of configurations which configure the communication device to communicate with the second BS 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 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 for the communication device ; receiving a SN Addition Request Acknowledge message in response to the SN Addition Request message from the second BS , wherein the SN Addition Request Acknowledge message comprises a first plurality of configurations which configure the communication device to communicate with the second BS 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 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 . <EOS>