I think you’re reasoning from the idea that there is a source of I-ness which is somehow separate from your physical self. Why, you seem to be asking, is this I-ness attached to this particular body at this particular time?
Firstly, there is no direct evidence that there is such an I-ness. Secondly, if there are other selves at other places and times, there’s no reason to suppose that they don’t have a similar experience to the one you have here and now.
I think you’re reasoning from the idea that there is a source of I-ness which is somehow separate from your physical self. Why, you seem to be asking, is this I-ness attached to this particular body at this particular time?
Firstly, there is no direct evidence that there is such an I-ness. Secondly, if there are other selves at other places and times, there’s no reason to suppose that they don’t have a similar experience to the one you have here and now.