Laptop Roaming profiles

All the users in our domain have roaming profiles. When a laptop user makes changes to their profile at home, then come in and log on to the domain, it reverts the files on the laptop back to the last time they were on the domain.

Some of our users are gone from the office for weeks at a time, so sometimes they lose weeks of data.

I really need help on this, its a huge issue at our company.