Nothing has changed and you can log in as always without having to re-enter details.
You may have not accepted cookies (that's what our cookies are for) or have something else on your PC that is logging out when you leave the site. Did you remember to click 'Remember me' on login?
I have checked your details and all works fine.
Can I suggest you try another browser or PC as a test - make sure to accept cookies, and try again?
If so try clearing cache in your main browser, reboot and log in again. As long as you accept cookies auto login should work fine.
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