[[Error]: buildin_getcharid: Player with nick '' is not found]

Hello, im getting this error in the console about this part of the script

 

// Now lets kick everyone else out!
        for (set .@i,0; .@i<=$avthana_countusers; set .@i, .@i+1 ) {
            if ($avthana_winnerparty$!=$avthana_mapusers$[.@i] && $avthana_winnerparty$!=getpartyname(getcharid(1,$avthana_mapusers$[.@i]))) {
                getmapxy(.@mapname$,.@mapx,.@mapy,BL_PC,$avthana_mapusers$[.@i]);
                if (.@mapname$=="thana_boss") charcommand "#return "+$avthana_mapusers$[.@i];
            }
            // Get rid of the data at the same time!
            set $avthana_mapusers$[.@i],"";
        }

        // All done. Lets remove the data.
        for (set .@i,0; .@i<=4; set .@i, .@i+1 ) {
            set $avthana_seal$[.@i],"";
            set $avthana_party[.@i],0;
        }
        set $avthana_countusers,0;
        set $avthana_winnerparty$,"";
        set $avthana_winner,0;
        
        ////////////////////////////////////
        /// BACK TO NORMAL THANATOS CODE ///
        ////////////////////////////////////

        monster "thana_boss",140,217,"Despair",1710,1,"#Death::OnWave";
        monster "thana_boss",140,216,"Hatred",1709,1,"#Death::OnWave";
        monster "thana_boss",141,217,"Misery",1711,1,"#Death::OnWave";
        monster "thana_boss",141,216,"Agony",1712,1,"#Death::OnWave";
        disablenpc "Crest#5";
        close;
    }
    input @input$;
    mes "^3355FFNothing happened.^000000";
    close;
}
 

anyone know how to fix it?