Q: Calendar deleting notes and events

Okay so multiple times now I have sat down for about an hour and added events with notes on the event for a whole year ( i.e.: paydays and bills due over the next year and notes on paydays about what bills to pay etc. ) a few days/weeks go by and everything is fine. Everything shows up on my MacBook calendar, iCloud calendar, and on all my iOS devices. Then all of a sudden events are missing and all of the notes on remaining events are deleted. I am at my wits end with wasting time entering this information. I am use calendar and all my productivity stuff to stay as paper free as possible and keep my "life" portable as it were. Does anyone else have this issue and have you been able to resolve it? Its happened to me on iOS 6 7 and 8 and on OS X mavericks through yosemite so I don't thinks its just the system issue. I think it may be with iCloud but honestly I don't know.  Also I have tried entering the information through the Mac first. second time was my iPhone then went to iCloud.com and entered everything in the calendar there. Still happens no matter the entry method. Any suggestions would be much appreciated.