Numbers not synching across devices
I continue to run into a synch problem with Numbers. I have a spreadsheet that I update regularly, but when I open it, it regularly shows more than one spreadsheet and says they are out of synchronization and I need to pick one. the latest message was similar, but showed spreadsheet options for sheets last updated over one month ago. I have regularly updated the sheet almost every day.
devices are ipad and iphone 6plus with current software (8.1.2)
thanks in advance
jim
iPhone 6 Plus, iOS 8.1