your html is a mess. IDs are supposed to be unique, but you have given the same one to every input box you have
the datepicker works with IDs, so if you use this:
Code:
$("#input-two").datepicker({
it will work, but on the first field that has that ID (Bedrijfsnaam
give your inputs unique IDs and if you want to style them all the same, that is what class is for so they can all have the same class name. Then the datepicker will work by supplying it the id of the element you want it to work on