I have been a member since 2011. I tried to look at my statistics for my activity/posts that go back to 2012 forward and discovered my posts only go back to 2016. Is there a way I can still see my old posts?

Reason I am asking is that I am being accused of doing something I never did and I was really struggling during this period and spent a lot of time posting here are PC. If I can show I was here, home and posting it will be proof I was not doing what I am accused of doing.