Keep getting an exception of "ORA-00971: missing SET keyword" where SET keyword is there.

Keep getting an exception of "ORA-00971: missing SET keyword" where SET keyword is there.

Hello friends,

I keep getting an exception of "ORA-00971: missing SET keyword" for the following source code. I have no idea why. As you can see, it has SET keyword.

Any ideas? Thank you so much!

            try
            {
                OracleConnection connection = new OracleConnection(_connectionString);
                connection.Open();

                using (OracleCommand cmd = connection.CreateCommand())
                {
                    cmd.CommandType = CommandType.Text;
                    cmd.CommandText = "UPDATE dis_web_gifts.ADVANCE.AWC_GIFT_TRANSACTION SET GIFT_AMOUNT = :amount_p WHERE AWC_TRANSACTION_ID = :trans_id_p";
                    cmd.Parameters.AddWithValue("amount_p", Amount);
                    cmd.Parameters.AddWithValue("trans_id_p", awcTransactionId);
                    cmd.ExecuteNonQuery();
                }
            }
            catch (Exception ex)