Top-Down SLA Printer Bulging Issue
Let's look at the problem mathematically:

The bed has a 0 that puts the surface some distance $d_0$ above the surface of the resin, the wiper does put the first layer on that height.
after curing, the printer moves down distance $d_d$ to coat the top surface.
afterwards, the bed lowers back up to $d_0+d_l$ - a thickness of 1 layer lower, or in other terms, it moves $-(d_d-d_l)$

Now, how is it implemented in your G-code? check that!