Thanks for reaching out!
Could you please let us know which endpoint you're using to create a card? Also, please send over a screenshot of the full error you're getting. I'm not familiar with error 100 in our API.
You can find all our status codes here: https://developer.atlassian.com/cloud/trello/guides/rest-api/status-codes/.
I'll keep an eye out for your reply,
The Trello Team
Ok, this is not an error, it is a warning. We made a public app and we don't keep track of which device send the data, so we don't know the endpoint.
Thank you for your help, knowing that it is not an error but a warning, we already have everything under control. Thank you very much for your help.