Hi, I’m pretty new to the whole 3D printing scene. I have a model which was created in blender, I then export it as an stl and import it into Meshmixer to add supports. I’m planning on sla printing it. However, when I upload it to 3dhubs or even import it back into blender, the quality changes and all the smooth edges go? It looks very blocky. How do I fix this?

Thanks