Try this code:
if connected() then
LAST_MANA = LAST_MANA or mp()
LAST_LEVEL = LAST_LEVEL or level()
local current_mana = mp()
local current_level = level()
if (current_mana - LAST_MANA) > 1 and current_level == LAST_LEVEL then
playsound('default')
flashclient()
LAST_MANA = nil
LAST_LEVEL = nil
pausebot(true)
else
LAST_MANA = current_mana
LAST_LEVEL = current_level
end
else
LAST_MANA = nil
LAST_LEVEL = nil
end