Please mark the Physical Surface and Curve with numbers, not strings. As you can observe by inspecting the boundary.xdmf file the values on each boundary is not 1 and 2, but 2 and 3, and does not consist of the whole circle.
This is because you are converting all the data written in with meshio.
See for instance: Transitioning from mesh.xml to mesh.xdmf, from dolfin-convert to meshio - #104 by dokken
or Mesh generation and conversion with GMSH and PYGMSH | Jørgen S. Dokken
for how to convert a meshio mesh and corresponding boundary data in a safe way.
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