Common misconception regarding "Last Log In"
Activity HAS to take place on the site for the Last Log In to update. So, sitting with the window still open without touching it will not trigger the last logged in. Even just navigating to that windo without action will trigger the last logged in.
My recommendation:
Send a private message today. See if the last logged in changes tomorrow. If they haven't responded by then, assume they saw your message and are ignoring you (for whatever reason). If they don't respond, move the transaction to either problem or unfinisghed. It will drop from your list in 90 days. You might want to just remove the cards from your collection now and not wait.
-- Dan --
Note: Please see my profile for more info regarding trading (section updated 3/4/2024). I have added a large portion of my inventory to the site, and currently have trading turned on (details are in my profile).