Get out and about for face to face networking every day. Hand out cards and ask for referrals everywhere you go.

When in the office, stay on the phone until your appointment schedule is full. 

In my former life, I trained people in the art of sales.  I've found the best technique was to have a stagnant sales person teach a segment that I felt they needed to improve upon themselves.  In doing the research necessary they caught the enthusiasm that was lacking.  What you think about, you bring about.

I would have them focus on an abundance mentality and the laws of attraction.

I meditate and pray for a direction.  Then I would really dicussion what I want out of my career and what I am willing to put into my career.   It even might be worth speaking with a real estate coach.

Learn, start learning a lot of marketing, advertising, branding for free online followed by mastering Google and Faceook Ads. Takes time to learn but it pays of huge.

I would create a niche - be the expert, focus the target and rebrand behind that.

Debbie Reynolds Get back to basics. If the enthusiasm is gone, there may be a career change in the future.

I would first try to determine why the career is stagnant.  Something is being done wrong.  Then fix the problem and continue.

I would follow Susan Emo 's suggestion, and do a complete makeover brand wise that would reflect the new vision, determination, and coming out in the world.  A

Open houses for everyone in the office every day of the week.

Attend Expert Agent panel presentations, actively blog and comment on Active Rain, take live education classes, work with a newbie...

Start calling past clients

Door knock

I'd say: go for a change. Some people( agents) too are waiting for business to come to them, but things are different now, you are responsible on finding  the way of forwarding business your way.

Insanity: doing the same thing over and over again and expecting different results.  Albert Einstein

Have them join Active Rain and read the blogs of Debbie Reynolds 

Lots of good suggestions in this thread. I'll add rethink you niche marketing. Maybe you're better suited for a different niche or not taking advantage of things that have changed, what you can highlight about yourself now compared to the past.

Good question Debbie, I am enjoying the answers, especially Susan Emo 's.

Figue out a new direction. I am sure it's not lacking skill or experience but I recommend a different tactic and taking advantage of your knowledge and sharing it with a new type of client. 

I would go out into the public and introduce yourself to as many people as possible. I would provide them with a general piece of information regarding current market conditions or any other valuable piece of information. Contact everyone you know and ask them "who do you know that might be interested in buying or selling a home?". Be visible!