I need some help

[u/RavenLoch51]

I’m playing Skyrim and I’m doing the dawnguard quest (vampire side). I think it’s buggy because I can’t get to the undercroft of volkihar castle to get to Valerica’s laboratory. Could it be the mods in my list? Can someone please help me and explain

[u/vastaril]

What do you mean, can't get there? What's getting in the way?