Texture Paint creates vertical distortions at a certain area of the model

Hi there

I do have a question regarding using Texture paint in Blender for the first time.

While painting on a 3d Model (not the 2d space) there is a vertical distortion visible at a certain area of the 3d model only.
It looks like a ring that spans around the torus. I do suspect something like a seam that causes it but I don’t know how one could solve the problem.
Unfortunately I cannot upload the .blend file due to filesize limitations.
Please find pictures attached and many thanks!