" k points are from 1 until 10",so you know they are points, not k values. From 0 to 05 kmax it has 10 points, you should be able to convert to actual k values. Please check the script in "model":
The kx in sweep is the point, and the actual kx is shown in the script.
For the modes, please check if you have used symmetry BCs to avoid one of the modes. FDTD solves Maxwell Equations, as long as the dipole and time monitor settings are proper, plus the boundary, you should be able to fid the modes. It is difficult for us to diagnose with simple descriptions. Please read the examples, understand how does the band structure is calculated. Using ready-to-use tools can lead to problems that the physics is missing.
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