Re-cookie a lead

Unfortunately, you can't "recookie" manually.  This has to happen on it's own when the person clears their cookies.  On the other hand, it does sound like you have an issue that needs to be addressed with your sales reps; getting them to stop with the reuse of emails meant for someone else.  How does that happen?

You should either have the employee delete the "_mkto_trk" cookie associated with your domain or send them an email from Marleto with a tracked link and have them click on it, which will reset their cookie to point to the correct lead record.

I just want to clarify this answer.

It is clear that the employee's cookie will be updated and point the the correct record when you have them fill out a form or click a link on an email addressed to them...so what happens to the original lead?

Will the cookie on the original lead's computer still work?  Or will they have to click on another email link or fill out a form to continue tracking?

The cookieon the original lead's computer should still work and point to their lead record.  It never hurts to send out emails that encourage people to click a link to ensure that they are properly cookied since many people clear their cookies periodically.  That's why a lot of companyies send email promoting contests. :0)