When a batch is created, it is automatically assigned a site if a site has been specified in the batch template. If no site is specified, it will be assigned "All Sites." However, if a batch is created with a specific site, and then other fields are subsequently assigned custom default values for that specific batch, the site for the batch will change from a specific site to "All Sites."
Download and install the latest patch, which contains all fixes from previous patches. If you are running an older version, download and install the latest version and then the patch.