Database: chicago_crime
Question: What is the fax number for the district with the most number of crimes in January, 2018?
SQL: SELECT T1.fax FROM District AS T1 INNER JOIN Crime AS T2 ON T1.district_no = T2.district_no WHERE T2.date LIKE '%1/2018%' GROUP BY T2.district_no ORDER BY COUNT(case_number) DESC LIMIT 1