Why can't I use my command in DM? | interactions.py | Page 1

I can only use it in guild

Here is my code:

from interactions import (
    Embed,
    slash_command,
    SlashContext,
    Extension
)


from fac_lib import functions
file_path = 'commands/help_commands.fac'

class help(Extension):
    @slash_command(
        name="help",
        description=functions.read(file=file_path).get("help"),
        dm_permission=True,
        default_member_permissions=None
    )
    async def help_function(self, ctx: SlashContext):
        print("/help executed!")

#Why can't I use my command in DM?