Can't go to the cathedral after beating it lives.

[bolasto]

I have this issue that makes it impossible to get the beam of light to shoot down from the sky when i beat it lives. Someone help me!

[The Renderer]

Are you sure you are beating "It lives" and not "Mom's heart"? What exactly does happen when you kill "It lives"?

The only other reason I can think of is you are using a mod that's breaking it.

[Tax evasion]

If you're getting only one entrance (Sheol, for your case, or nothing at all), I can only suggest you beat Mom's Heart and got unlucky, because It Lives guarantees both portals, as well as a Hush entrance if done under 30 minutes.
To unlock It Lives, you need to beat Mom's Heart 11 times.
Or, as said above, mods cause it to break.

[bolasto]

thank you all then it must be cuz of the mods
:)