try

fraction = 512
basebet  = balance/fraction
nextbet  = basebet
bethigh  = false
chance   = 24
target   = 5000
james    = balance
zim      = 0
zye      = 0
lye      = 0
fim      = 0
resetstats()
function dobet()
    if win then
      fim = 0
   else
      fim+=1
   end
  if (fim==8) then
      nextbet = previousbet*2
      fim     = 0
  end
   if (nextbet==null) then
       nextbet = previousbet
    end
   if balance>james*1.2 and win then
       nextbet = balance/fraction
       james   = balance
         fim     = 0
   end
   if nextbet<= basebet then
       nextbet = basebet
   end

if balance>target then
    stop()
end
end