Incorrect Syntax near SqlQuery

Hi

 In below code i am getting error "Incorrect Syntax near SqlQuery

DECLARE ColumnNames nvarchar(100);
Declare SQLQuery nvarchar(100);

SELECT STRING_AGG("U_A_M", ', ')  
FROM (SELECT DISTINCT (T2."U_A_M")
            FROM Oitm T2) As cols;

SET SQLQuery =  'SELECT itemcode, ' + cols + ' from
            (
                SELECT T1."ItemCode",T1."LineTotal", T2."U_A_M"
    FROM Opch T0 inner join Pch1 T1 on T0."Docentry" = T1."DocEntry"
	inner join Oitm T2 on T1."ItemCode" = T2."ItemCode"
	where T2.U_A_M <> ''NA''
           ) x
            pivot
            (
                 sum(linetotal)
                for U_A_M in (' + cols + ')
            ) p '


execute(SQLQuery)

Thanks