I cant upload files with ftp

When I try to upload a file from the FTP file manager online and from FileZilla it happens that the file manages to upload but it is instantly deleted

I used translate
I speak spanish

I have a file in the directory “public_html” called “Do not upload files here”

You should upload files to htdocs folder

Did you check this article already? https://infinityfree.net/support/why-are-my-files-deleted-after-uploading/

If that doesn't answer your question, can you please describe what kind of files (file type, extension, size) you're trying to upload and where you're trying to upload it to?