Problem writing a bot in python via pytelegrambotapi?

Question

Python

import telebot
from telebot import types
from telebot.types import InlineKeyboardMarkup

bot = telebot.TeleBot('token')

@bot.message_handler(commands=['start'])
def get_info(message):
keyboard = types.InlineKeyboardMarkup()
key_buy = types.InlineKeyboardButton(text='Paid', callback_data='/buy')
key_free = types.InlineKeyboardButton(text='Free', callback_data='/free')
keyboard.add(key_buy, key_free)
bot.send_message(message. chat.id,'I'm online. Which subscription will you use?\n Paid subscription (129 RUB/month) or free subscription is available. For details write /help.',reply_markup=keyboard)

@bot.callback_query_handler(func = lambda call: True)
def subscribe(call):
if call.data == '/buy':
send = bot.send_message(call.message.chat.id, 'Bla a')
bot.register_next_step_handler(send, subscribe2) Throws from here
elif call.data == '/free':
bot.send_message(call.message.chat.id, 'You are using the free version, but you can always buy the paid version from us. Details about it: /help.')
bot.answer_callback_query(callback_query_id=call .id)
def subscribe2(call): Here
keyb = types.InlineKeyboardMarkup()
key_no = types.InlineKeyboardButton(text='No', callback_data='no')
key_yes = types.InlineKeyboardButton(text='Yes', callback_data=' yes')
keyb.add(key_yes, key_no)
bot.send_message(call.message.chat.id, 'You have chosen to buy a subscription. It costs 129 rubles per month.\nAre you sure?', reply_markup=keyb)
if call.data == 'yes':
bot.send_message(call .message.chat.id, 'BUY')
elif call.data == 'no':
bot.send_message(call.message.chat.id, 'free')
bot.answer_callback_query(callback_query_id=call.id)
bot.polling ()

The bot should ask a question with the keyboard about the subscription, after clicking on the Paid button, a confirmation opens, after clicking on the Yes button, the following function should be displayed, but it is not displayed. Please point out the error.