you need to give a much more detailed post then this. things like breed, what are they eating, how old they are. Everything you add in terms of information helps. until then the only thing people can do is guess and thats not a good way to start.
i have saanen dairy goats they eat 18% dairy pellets just started giving them this a couple of months ago and alfalfa hay started giving this 2 mos. ago i have trouble with my young goats 3 to 6 mos. old they dont grow very good and take diareah and in 2 or 3 days die for no reason i worm them give their shots still doesnt help what to do rush
Just giving them "a wormer" doesn't guarantee anything. There is no one wormer that takes care of all worms. You need a fecal done so you know which worms you are dealing with. Then you can be sure you are using the right wormer.
Just as important is giving the proper dosage. There are almost no dewormers that goats get the label dosage. Most of the time they need a higher dosage.
Also important to know the weight of the goat. Most people's guesses are usually way off and underdosing a wormer will only build resistance.