As per ASI report, it reads "The period of Ramayana is considered as Tretha Yug (more than 17,00,000 years ago). The study, however, concluded that the Adam's bridge is not man made in nature.".
We can hear from people about happenings before 2000 years. Is it possible for an evidence to stay for these many years? (Some reports suggests 880,149 years) Also for the report that stats the bridge is by nature and not man made, please understand that even carbon will turn into Diamond in course of time.
It is possible for a man (RAM) made bridge into a natural formation in these many years.
Moreover, this is not only a matter of scientific evidence, but a matter of billions of followers.