Few months ago it was fairly easy to get a Diviac Premium account for life for free . All you had to do was to invite two or so of your friends (e-mail addresses) to register a (free) account.
However back then for several months Diviac had a serious problem. The "reports" page where several important things are shown (like SAC rates, dives per place/buddy/month, type of dive etc) was not working.
Over the course of few months I did write several e-mails letting them know and I kept getting a reply that they are aware of the problem and that they are trying to fix it.
Following that, I decided to look for better alternatives and I came across this brilliant piece of software called subsurface. It supports downloading from most (if not all) dive computers, offers online/cloud storage of your logs, and it has a lot of other brilliant features like the ability to use different (open source) deco algorithms with several options (GF etc) on your actual dives or for planning purposes. Did I mention the best? It is totally free!! Give it a try.