I just switched over from PIA to Mullvad like last month or so. Really surprised that Mullvad asked for literally no information from me - no username, password

I just switched over from PIA to Mullvad like last month or so. Really surprised that Mullvad asked for literally no information from me - no username, password, email etc. I'm setting reminders on my calendar to remember to add more time to my account, but other than that, VPNs shouldn't have more info than that. More on topic: Doesn't say on the page, but does the card ever expire?