Drupal 8 Ajax Callbacks misbehaving when form element in table
It's hard to tell without seeing some code of the table. There is probably an error in the structure of the form array. All form elements must have the correct key in the array, which correspondent with the #name. And this keys and names must be unique in the whole form. If you put a form element in a table, use an extra layer to give the element the right key.