I have a table, and i declare a cursor to get average price from the table,but cursor does not work correctly , please help me

id      CurentSock  UnitPrice
16	20.00	    0.25
16	120.00	    0.32
16	30.00	    0.35

declare @count int
declare @sum decimal(18,2)
declare @currentStock decimal(18, 2)
declare @result decimal(18,2)
declare @itemID int
declare @unitPrice decimal(18,2)
declare @totalUnitPrice decimal(18,2)
declare @avgUnitPrice decimal(18,2)
declare @totalOrder int

set @count = 0
set @sum = 0
set @currentStock = 0
set @unitPrice = 0
set @totalOrder = 120
set @totalUnitPrice =0

declare FIFOAVG cursor local fast_forward for
SELECT 
	 [ItemId]
      ,[CurrentStock]
      ,[UnitPrice]
    
  FROM [Nimble].[dbo].[Proc_ReqSlave]
   where  [CurrentStock] <> 0
   AND
	[ItemId]=16
 
  open FIFOAVG
  
  fetch next from FIFOAVG into @itemID,@currentStock,@unitPrice 
 
  while @@FETCH_STATUS = 0
  begin
  
  IF(@totalOrder > @sum)
 
  BEGIN
	  set @sum = @sum + @CurrentStock
	  set @count = @count + 1
	  set @totalUnitPrice = @totalUnitPrice + @unitPrice
  END
  	
  fetch next from FIFOAVG into @itemID,@currentStock,@unitPrice  
  end
  
  set @result = @sum/@count
  set @avgUnitPrice = @totalUnitPrice / @count
  
  close FIFOAVG
  deallocate FIFOAVG
  select @itemID
   select @totalOrder as 'Total Order'
  select @sum as 'Sum'
  select @count as 'Count'
  select @totalUnitPrice 'Total Unit Price'
  select @avgUnitPrice as 'avg'

Total Order 120
sum 140
count 2
total price 0.57
average 0.29

sum 170
count 3
total price 0.92 and 
average 0.31