That’s the seam for each layer. You can change a few settings related to it but you probably won’t be able to totally get rid of it. The “Random” position setting will make it disappear but it’ll get scattered over the top of your plug.
That is the seam. I don’t know much about the options around seams but that is what it is.
You might try the different options, run through the slicer and see if you can arrive at a better look.
Assuming you are using PLA or PETG, you can now use the Scarf settings per filament type. This can be used with other filaments, but experiment for safety first.
Use the edit option next to each filament in the filament chooser from the prepare tab.
The problem is the nature of FDM. The start and stop points are in the same place, meaning, these get slightly more material. Using the Scarf settings, you can tell the slicer to use a ramp up at the start and ramp down at the end.
Visually, this improves things.
Used with shiny materials like silk, it becomes too obvious and defeats the purpose.
You can see/hide the seam effect, normal or by using the scarf with the toggle when in filament view.