There was an original estimate which was low. ("The deaths of 64 people were initially directly attributed to the hurricane by the government of Puerto Rico")
Groups began re-evaluating the numbers and extending deaths past the actual hurricane claiming these people died as a result of the hurricane.
It went from 64 to 3000. People are probably still dying from Hurricane Maria.
The 64 number was the official number of dead, aka bodies.
All other numbers have been estimates, a computer simulation/program developed to estimate deaths based on not having proper infrastructure after the hurricane, the time period was for 6 months after the hurricane.
The numbers are fake since they are not counting bodies but imaginary people who might have or could have died.
64 is still the official number, everything else is political BS