nissan almera tino, taking in air through fuel filter

my car will not start in the morning or if i leave it for a few hours, i
have to prime the fuel filter and then it takes a while to start, after
that it starts perfect each time till i leave it again, someone said the
fuel is running back out of the filter and some have said its letting air
in, any ideas of what it could be and how to fix, thanks.

vicki