on_member_join can’t print a message

  discord, discord.py, python-3.x

i’m doing a Discord bot with python 3.8 and i have a problem with my function on_member_join()

async def on_member_join(member):

    embed = discord.Embed(
    title=f"that doesn't function")
    channel = discord.utils.get(member.guild.channels, name='WELCOME_CHANNEL_NAME')

    await member.send('Hello')
    await channel.send(embed=embed)

my member.send function (send a private message with hello) but channel.send send this error await channel.send(embed=embed)
AttributeError: ‘NoneType’ object has no attribute ‘send’

I really don’t know how to do,

Thanks for your help!

Source: Python-3x Questions