Cant make backup

Hi there, I recently moved my grav to another server. Since moving it I cannot make any backups.
After clicking make backup I get this error: An error occurred. ZipArchive::close(): Can't open file: Permission denied.

I tried changing the CHMOD settings using FTP, but it's still not working! Is it a problem with the server settings? How can I fix this?

Thanks
Chuch

Check out the Permissions Guide, it's likely an issue of your web server not able to write to the backup folder