Is this a Bug? How can I Fix it?

[Zyntic]

Hey guys, Can someone explain to me whether this is a bug?
I can edit it with the clay/brush tool until it is no longer visible, but as soon as I smooth the surface, this edge reappears. Is this a bug in the mesh? How can I fix it?

Edit: I used a UV Sphere for the head and a tube for the neck at the beginning. Afterwards I joint both together. So right now the model is one part.

FYI.: I use the Desktop Version of Nomad.

Thanks

greetings max

[Zyntic]

EDIT:

Just used the Voxel Remesher and repaired the topology.

I worked from the beginning on with DynTopo and joint the UV Sphere for the head and a tube for the neck together. That causes the edge between them.

So for now I just start with Voxel and for final stages I will use DynTopo.