Battery drain since version 2.8 on samsubg A5

hello, since installation on 2.8, then 2.9 my batterie life go from 3 days in hard saver mode to less than 1 day.
I erase version 2.7.
is it possible to force to re-dowload it to reinstall it ? if yes how.
is my A5 the only one to suffer from this behavior ?
any idea to solve this issue.
regards