Event that 'execute' on owner (or Specific client) only?

Hi , I am trying to find a way to tell the client players to load or save their SaveGame ,
therefore I need an event that could called by Server , but execute on the owner himself , and only himself ,

and I already know that Key input or Widget is some good way to trigger local only event ,
but what I need is to trigger by server but tell the player to save or load at anytime I want , and having a problem ,
even I tried calling “Run on Owning Client” the event still been execute by multiple clients for multiple times ,

what I want to do is , that I call an evnet in Pawn1 or PlayerController1 , then the Client1 execute the event only ,
If I call the same event in Pawn2 or PlayerController2 , then the Client2 do the same , and no others was involved .

well so I need some help for this , anything would be helpful , thanks .