Criterion 1: A candidate can attempt JEE (Advanced) a maximum of two times in consecutive years.
Criterion 2: A candidate should have appeared for the Class XII (or equivalent) examination for the first time in either 2017 or 2018.
As per above two conditions you can only attempt JEE Advanced only once.
However, if your Class XII examination results for the academic year 2016-17 were declared after June 2017, You may be eligible to appear in JEE (Advanced) 2019 as well.
*Please note that the eligibility suggested to you is based on this year criteria, there may be chances for upcoming exams.