Mantaflow use in blender .Blend file
I am a blender beginner and after watching some tutorials online I figured I'd give modeling and animation a try.
I am trying to make an oil hourglass animation that will move the liquid downwards.The hourglass is exactly the same as the one shown here, I have a physical reference of it.
The only issue is that my liquid doesn't seem to want to pass through 2 holes I made on the container mesh, I suspect it's because of the wrong facing normals right outside of it:

I managed to get the liquid to flow inside of the top sphere.

but It won't flow into the rest of the mesh.

Will I have to create a new mesh? Help is appreciated, thank you!
The first thing to note is you need to ensure that your domain resolution is set high enough so you have enough fluid detail to fit through any holes. Look at the small cube in the bottom corner of the domain - visible in your second image; that’s the size of one ‘cell’. Any hole smaller than the width of that will definitely obstruct your flow. Start by increasing the Resolution and/or increasing the size of your ‘holes’.
Also, make sure any obstacle meshes are Manifold (completely enclose a volume).