Getting fetch returns more than requested number of rows error SQL HANA SAP

[kanesamba]

Hello Can you please help me fix this query :

SELECT T1."Price" into pght FROM ITM1 T1 WHERE T1."PriceList" = '1';


UPDATE "ITM1"
    SET ITM1."Factor" = T2."U_COEFFICIENT" , ITM1."Price" = T2."U_COEFFICIENT" * pght
    FROM ITM1
    INNER JOIN OITM T0 ON T0."ItemCode" = ITM1."ItemCode"
    INNER JOIN OMRC T1 ON T1."FirmCode" = T0."FirmCode"
    INNER JOIN "@PR_MARQUES_ASSOCIE" T2 ON T1."FirmName" = T2."U_MARQUES"
    WHERE T2."U_MARQUES" = 'ROCHAS' AND T2."Code" = '01' AND ITM1."PriceList" = '2' AND T1."FirmName" = 'ROCHAS';

Actually my goal is to update the column ITM1."Price" where ITM1."PriceList" = '2' with the price Value where the "PriceList" = '1' * factor

For exemple ITM1."Price" and "PriceList" = '1' = 40 $ ITM1."Factor" = T2."U_COEFFICIENT" = 4

Then ITM1."Price" and "PriceList" = '2' = 160 $

i tried the above query (in the body) and i think its not correct