Sometimes certain versions of what you’re trying to download may only work with certain versions of iDevices. Cydia is an unofficial app store, so many downloads may be unreliable and unstable. Often times, the author of the app will include whether or not the download will work on your software version. This is true for the Apple store as well. If your operating system isn’t listed on the app, then I recommend not using it.
Did you try deleting, then re adding the source? I If that doesn’t work, then you might have to restore the iPad. Be sure to back it up before you do.
Also you could try searching some forums on your issue, as I am not tech savvy so I don’t want to steer you in the wrong direction. Try searching, “Package needs to be reinstalled.”