Period Deleted???

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I’m very upset. I think I just accidentally deleted one of my past periods.

Background Info: I’m 26 and always been irregular. I started using this app 2 years ago to help me record my actual periods. I was just viewing my list of periods and saying “wow I only had 4 periods last year” I showed my partner and when I turned my phone back around only 3 periods were listed for 2017. What the heck.. I saw little purple minus signs and thought I must have accidentally touched it.. I shook my phone but it wouldn’t undo.. I’m very upset.. It took me a whole year to record that data and now it’s gone.

Is the purple minus sign what deleted it?? Can you please make it so that it’s not so easy to just delete any records...