Have you made sure that none of your villagers are sick? If they get sick, and you don't heal them, they will lose health and die. You should also make sure that some of your villagers are researching at the research table so that you can buy Level 2 of Harvesting as soon as possible - the berries run out! You could also try playing the game on easy setting and running your game on slow speed until your villagers are doing well. That will give you more favorable conditions to start with.
_________________________
Barbara
Unicorn
Last Day of Work