Is it 3weeks since the 1st treatment? Coccidia lifecycle is 3 weeks, so if they are still in the environment (bedding etc) they will just be overcome again, even if the reading after the 1st treatment was low.
So another treatment with Vecoxan or Baycox would be my 1st action, as well as taking off grass & concentrate for a couple of days. PLus a full mucking out, and using some disinfectant (powder or wash) like Stalosan (other cheaper brands are available, anything for dairy cattle is usually good enough)
But also goats can get viral diarrhoea too, and AB's will not really make any difference to those.