I'm having the exact same problem. Using Safari in macOS Sequoia 15.3.1(LastPass for Safari version 4.139.0)
I tried selecting the auto-login option but it doesn't keep the option ticked on whenever I restart.
Anyone got any other ideas?
I don't know how but now all of a sudden it's working for me. No more logging me out whenever I shut down my Mac and having to retype my master password every time. Maybe LastPass did something their end to help me out. If that's the case, thanks LastPass!