Time Capsule backup lost on update

I have a Macbook Air and a Time Capsule A1409 model.

I use this Time Capsule to save a good part of my files, cause the Macbook Air HD has a very limited space for files (120 GB) and I could access then via wifi.

For this use I created a folder on the Time Capsule root, besides the one automatically created for Time Machine Backups propose.

On May 1st, Time Machine asked for an update that should be done. As a result of this update, all my Time Machine backups were lost (the older files are dated on May 1st) and all my files at the separated folder were also lost.

Someone can help me how to recover all my files and the Time Machine backups (if possible).

Thanks.

Téo