Retrieving Max / Latest Date From A Table With A Join To One Another Table

I am having trouble retrieving the Max, latest date, from a table with a join to one another table and other fields from both.I was able to get the MAX service_date grouped by id. But once I tried to add more fields to the query and another table it won't work.

Here is what I have:

selectMAX(cs.service_date), cs.notes, cs.applicant_id,wr.program_code,wr.last_name,wr.first_name,wr.region_code,wr.status_cd
from cs join wr on cs.applicant_id=wr.applicant_id
where wr.status_cd='AC'
group by cs.applicant_id