I'm trying to connect two shapes in blender but whenever I try to connect the vertices, whether it's through merging them individually (alt + m), using the bridge tool, or through Remove Doubles (now called Merge by Distance), the vertices behave as if they aren't being affected by the subsurf modifier. Here's the shape without the modifier on:
Turning the modifier off or removing it, merging the vertices, then adding the modifier back still causes the same error. I assume this is a bug but I want to know if there's something I'm missing. In the meantime I suppose I'll have to model the entire shape as one piece.