curl --location 'https://api.even3.com/api/v2/checkin/attendees' \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '{
"attendees": [
{
"check_in_code": 999999,
"is_checked_in": true
}
]
}'{
"message": "Data entered successfully."
}