Where can I find deleted reminders lists? The stupid phone has erase them 3 times out of the blue, anybody else having this problem?

In the last year I have had an Iphone 4S and the new Reminder app that comes with it. Three times this phone has just erased Reminders lists I had created. I thought it was due to being empty or reminders but this week 4 out of five lists disappeared from one moment to the next. I had entered a couple of reminder in the morning. When I came back to my office in PM and open the reminder app: 4 lists gone!! some of them with 3-4 items in them!!

My other phone a 3GS has deleted some of my "NOTES" in the notes app in the same fashion. I lost very important phone numbers and lists of passwords from one day to the next and Syncing didn't help that or the Reminder problem. It looks like a repeating problem in different generations. I never had these problems in my old Treo and it was not that SMART!!