Weird pixilated lines between static meshes

Hey everyone, hope you’re all doing well. I’ve been working on a clone to the popular game called stack. In many cases, there are these white lines that appear between where the two surfaces meet. It happens a lot, but is weirdly inconsistent.

If anyone could recommend a way to make these artifacts go away, I’d be very grateful. I’ve attached an image of what I’m describing. It is visible in the bottom left.