I am trying to update (using Inner joins for three tables) item stats `STAT` for table `IM_ITEM` by highlighting items that sold less than 12 as "D" (Discontinue). 

The 2nd table `PS_TKT_HIST_LIN` has the Quantity sold column `QTY_SOLD` for each item on each day and the date column `BUS_DAT`.

I also need a third table `IM_INV` to filter the data, I need to say the last received date `LST_RECV_DAT` for these items is earlier than "2019-01-01" and last sales date `LST_SAL_DAT` is after "2019-01-01". I used the following code

```
 UPDATE M
    SET M.STAT = 'D'
FROM
    dbo.IM_ITEM AS M
INNER JOIN
    IM_INV AS N
ON
    M.ITEM_NO = N.ITEM_NO
INNER JOIN
    dbo.PS_TKT_HIST_LIN S`
ON
    M.ITEM_NO  = S.ITEM_NO
WHERE
    CONVERT(DATETIME, FLOOR(CONVERT(FLOAT, N.LST_RECV_DAT))) <= '2019-01-01'
AND CONVERT(DATETIME, FLOOR(CONVERT(FLOAT, N.LST_SAL_DAT))) >= '2019-01-01'
AND M.STAT = 'A' 
AND SUM(case when DATEPART(YYYY, (BUS_DAT)) = DATEPART(YYYY, DATEADD(YYYY, -1, getdate()))
        AND DATEPART(yyyy, (BUS_DAT)) = DATEPART(yyyy, DATEADD(YYYY, -1, getdate()))
        then qty_sold else 0)<12

```

It comes with an error
Any advise please