Particle beam having a weird mark at the end

I’ve created a beam effect for the items loot drop.
But I’m having this odd effect at the end of the beam.

It has a cylinder mesh with a linear gradient material.
Does anyone know what might be the problem?

צילום מסך 2021-11-29 ב-22.58.24

The Render part contains a Mesh Renderer. Is it set to spawn a cylinder in the settings somewhere?