I used to have a trial license of Confluence, is there anyway to recover that?

[Adrien Ragot 2]

Yes, 30-days evaluation licenses are time-limited, but you can purchase a perpetual license for your server on my.atlassian.com.

[Nic Brough -Adaptavist-]

I'm not sure what you mean by "recover"?

If you've lost your access details, you'll need to go through resetting the passwords.

 If you really do mean the licence stuff, then you get an evaluation for a while and when it expires, that's it - either purchase or lose it (actually, Atlassian are more flexible and let you have a few extensions, but it's still purchase or lost it).  That's all handled in your OnDemand/Cloud account, the one you used to set up the trial.