Time has no substance or reality beyond that which we give it, in this life. Terms like "previous life" are irrelevant. There is only Life. And all life is one life. We are all just fragments of this one life, examining itself. We are not separate. We have no permanence.
However, we mostly live under the illusion that we are, that we do.
This self or identity, is just a construct, a device, built by the ego, which imagines itself (and therefore, our selves) central to all existence.
There are many ways to temporarily put the ego aside and experience the oneness of everything, but if you are unprepared, or come "thinking through the door", there is the very real risk that your "self" fragments as it assimilates a new "boot record". This is a scary place to be, and is inhabited by all your rejected demons and fears. Well worth the risk though, if you can keep your shit together.
To the Victor, goes the spoils. all the best, Napoleon Boneparte.