To summarize, lack of dew can be from what Tamlin indicated, as well as a shock to its environment, or insufficient lighting. What happens with most people is that they buy a long neglected plant from Lowes ("cube of death") and when they bring it home and take off the plastic dome, the change in humidity and/or temperature and/or light is enough to set it "over the edge". It may not die, but the change was enough to make an already sick plant worse. So the best thing to do is to have it acclimate to its new environment, gradually increasing the light and eventuallu keeping the dome off. I suggest removing the dome by day and cover at night, for a few days, and them keeping it off 24/7. You may have a different situation, but as long as you got the plant through the mail, even the healthiest plants, will be discombobulated for awhile. And it is rare for a received sundew to maintaine its dew, upon arrival. Provide the best conditions you can and give it time to recover.