Health app data lost

Hello.

Last week I had problems with adding some data to my Health app on iPhone 5 iOS 8.3. I've been adding Sleep tracking data manually for a long time now. But for some reason on Wednesday (April 22nd), I think, it was not working. I chose the time and date, set the duration of "In bed" statistics, but when I press done it just went to the Sleep tracking data and the was no new entry (I tried many times).

On Saturday I decided to give it one more try and when I opened the Health app I found out that all my Health app data was gone: sleep tracking, calories, weight, running. It was all gone. And just as with Sleep tracking I can't add a new entry.

On Thursday I tried Siri for the first time. I tried to turn off Siri. Still can't add data to Health app.

Have anyone encountered such problem? What might be th reason?

Thank you.