How can I move Gateway service cross client

Hi team

I created a gateway client in client 001. but we have to demo result in client 300, how can I move my service to client 300? I don't want to recreate the srvice

I tried to add sap-client=300 in Service url. I got the error message : No System Alias found for Service 'Z_XXXXX' and user 'XXX'. and I open segw in client 300, there is no project.

Thanks!