[Konstantinos]

You probably declare a variable in OnDialogResponse for dialogid 23 and its default value is 0. Store it to a variable:

pawn Код:

// global:
new Player_Clicked[MAX_PLAYERS];

// OnPlayerConnect:
Player_Clicked[playerid] = INVALID_PLAYER_ID;

// OnPlayerClickPlayer:
Player_Clicked[playerid] = clickedplayerid;

In OnDialogResponse, use Player_Clicked[playerid] (it will store the clicked player's ID) and reset it to INVALID_PLAYER_ID after done what you want with the list items from the dialog.