Hi ,, well that's a very trick problem hahahahah ,,i had the same problem with my bots ,i had made them for pvp , so they would fight with me and gang on layers who tried to get to me ,, and it was awesome ,, until i got reported ,,

... but heres how u do it ,
u have to keep the "do kill player " command -- as this will make ur bot walk to the player and attack him
now he will keep attacking him ,, so now the solution to this is open ur timeouts.txt
and make this changes
ai_move_retry 0.25
ai_move_giveup 1.5
# Send the attack packet every x seconds, if it hasn't been send already
ai_attack 1
ai_homunculus_attack 1
# Check for monsters to attack every x seconds
ai_attack_auto 0.5
# Give up attacking a monster if it can't be reached within x seconds
ai_attack_giveup 1
this will work wonderfully for your bot ,,,,