The agent is still activated but it's been so long since he was able to make contact for a mission that he's lapsed into one of the three basic flatlines, long-term survival strategies for agents in the field. He works a job with suitable pay, displaying aptitude but a lack of drive, keeps a suitable room, eats the basic foods, runs hand-to=hand combat drills in his room and trains at the YMCA. He still spends time in public trying to make contacts, but for three years no one's been able to correctly supply even the third stage of any of the seven-to-eleven part handshakes that he'd accept. So he despairs, but no matter what he's still waiting for orders. He doesn't know what to do without them.
What happened? Has he been disavowed and cut off? He wouldn't know why. Memories from old missions are only available as they become relevant to current missions. Was the agency destroyed? That might explain why no one's tried to pass him a fake handshake for some time now. Nothing left to infiltrate. He occasionally entertains the notion that he's on a deep cover assignment of some sort, but they'd have made him somebody else for that. He's just going about his day with a bare unmodified Agent personality. He wonders if this is unique. How many others like him might be out there?
He's still adept at what he needs to be able to do. Hardly anyone he passes on the street could give him any trouble. When he notices someone who could he checks to see if they're a contact. They aren't, and without a mission driving him he's got no reason to make an ally or enemy out of this person and he'll simply never see them again. This would be frustrating, unbearable to some, but he knows for a fact that the basic Agent personality will never get run down from loneliness or boredom the way someone else might. He'll function this way for decades.