Keynote problem

I am using Keynote on an ipad 2 with OS 8.3 and a windows laptop with icloud and I am suddenly having problems opening already created files. When I try to open on my ipad I get the message: Presentation can't be imported. The document was created with an unsupported application version. When I try to open the same file in icloud I get the message: Sorry something went wrong. This presentation can't be opened right now. Please try again later.

Any ideas why I am suddenly having this problem?