While running script for load users more than 10, getting NL-Network-02 error for POST request with content type-text?

Getting error while creating load for few request. Also added think time but still getting error.
Is there a way to resolve this wouthout adding think time. Error details are as below,

Error detected by NeoLoad
Error Code: NL-NETWORK-02 Message: Bind error connecting to server. Error attempting to bind a socket to a local address and port. Typically, the Load Generator cannot open more sockets on the local system.