I haven't noticed this "vanishing" either except that I've noticed a few deleted images by just a select couple of members.  Bipolartwo, I suggest you post this concern to the Community Forum and see if someone in administration can look into this. But be prepared to give more detail on who and when and where. That's the only way it can be traced.  But if this is happening as you say, it is a matter that needs correction.

Flannel Knight's Photos
MrsLubner
Forum Moderator
______________________
"It please me to take amateur photographs of my garden,
and it pleases my garden to make my photographs look
professional."
                                          Robert Brault