A method performed by an agent for handling an event of a network service deployed in a cloud environment is provided. The agent is capable to access to a server in the cloud environment. The agent obtains information from the server. The information is about an event of the network service. When the network service relates to a Third Generation Partnership Project (3GPP) network, the agent decides whether to register network service with or without an associated address of a load balancer of the network service. The agent then registers in a core network node operating in the 3GPP network, the network service with or without an associated address of a load balancer of the network service according to the event and according to the outcome of the deciding.