Walking NPC Error & Crash

[Snaehild 0]

Hi, I have this NPC walking around the center of Prontera but I often have this error and will end up crashing.

[Warning]: npc_scriptcont: failed npc->checknear test.

prontera,156,225,5	script	NPCWalking	811,{	mes "GM list : "+( .admincount + .gmcount );	mes "-----------------------------";	for ( .@i = 0; .@i < .admincount; .@i++ ) {		mes "^ff0000GM "+ .admin$[.@i]+ "^000000 ["+( ( isloggedin( getcharid( 3, .admin$[.@i] ) ) )? ( ( checkidle( .admin$[.@i] ) > .idletime )? "^eb43edIdle^000000" : "^2dd50cOnline^000000" ) : "^b5b5b5Offline^000000" )+ "]";		mes "-----------------------------";	}	for ( .@i = 0; .@i < .gmcount; .@i++ ) {		mes "^ff8c00GM "+ .gm$[.@i]+ "^000000 ["+( ( isloggedin( getcharid( 3, .gm$[.@i] ) ) )? ( ( checkidle( .gm$[.@i] ) > .idletime )? "^eb43edIdle^000000" : "^2dd50cOnline^000000" ) : "^b5b5b5Offline^000000" )+ "]";		mes "-----------------------------";	}	mes gettimestr("%I:%M%p ",10) + gettime(5) + gettimestr(" %B ",15) + gettime(7);	close;OnInit:	setarray .Message$," <3 ",				"Msg1",				"Msg2",				"Msg4",				" . . . ";	.idletime = 120; // idle for 60 seconds = idle status	setarray .admin$, "Snaehild";	setarray .gm$, "Boom", "Panes";	.admincount = getarraysize( .admin$ );	.gmcount = getarraysize( .gm$ );	startnpctimer;	npcspeed 200;	end; 	OnTimer15000:	npcwalkto 138+rand(5),208;	npctalk .Message$[ rand( getarraysize( .Message$ ) ) ];	end; 	OnTimer30000:	npcwalkto 127+rand(5),199;	end; 	OnTimer45000:	npcwalkto 150,185+rand(5);	end; 	OnTimer60000:	npcwalkto 156+rand(5),176;	end;	OnTimer75000:	npcwalkto 175,201+rand(5);	npctalk .Message$[ rand( getarraysize( .Message$ ) ) ];	end;	OnTimer90000:	npcwalkto 156+rand(5),225;	end; 	OnTimer105000:	stopnpctimer;	initnpctimer;	end;}