HELP! upload files

Hi everyone!

This is my first time to try to upload files. I am sure I followed all the steps. The end I got this alert “You must indicate you have suitable licenses/ ownership of the content you’re uploading”.

I don’t know where I miss or how can I indicate. Please help me, Thanks!

There is a checkbox close to the end, right before the upload button, which you need to check.

Saw the checkbox before. I thought it is the part of “message to review”, my mistake.

Thanks a lot!