aiogram.utils.exceptions.BadRequest: Unsupported parse_mode

from  aiogram import Bot, Dispatcher, executor, types
from currency_converter import CurrencyConverter
from aiogram.types import ReplyKeyboardMarkup, KeyboardButton
 
 
bot  = Bot(token='**')
dp = Dispatcher(bot)
 
def converter(sum,x,y):
    c = CurrencyConverter()
    return(c.convert(sum, from1, to))
 
@dp.message_handler(commands=['start'])
async def hl(message: types.Message):
    await bot.send_message(message.from_user.id, 'Привет! Что перевести?', reply_markup=greet_bt)
 
 
@dp.message_handler()
async def user_reply(message: types.Message):
    message1 = message.text
    from1 = message1[0:2]
    to1  = message1[len(message1)-2:len(message1)]
    await message.reply(message1[0:2],message1[4:6])#converter(s,from1,to1)) 
 
 
usdrub = KeyboardButton("USD to RUB")
rubusd = KeyboardButton("RUB to USD")
eurrub = KeyboardButton("EUR to RUB")
rubuer = KeyboardButton("RUB to EUR")
greet_bt = ReplyKeyboardMarkup(resize_keyboard=True, one_time_keyboard=True).add(usdrub,rubusd,eurrub,rubuer)
 
if __name__ == '__main__':
    executor.start_polling(dp)

await message.reply()

message[0:2]

 message[4:6]

messagestr=message[0:2] + message[4:6]
await message.reply(messagestr)