CST simulation problem

hello, when I want to simulate two separate objects and connect them with discrete port, the range of frequency is between 1KHz and 50KHz and the length of my objects are around 200mm. I can not simulate that because this error comes: The mesh representation of discrete edge port 1 is a single point.(Probably you need to increase the mesh line ratio limit for automatic mesh generation.)
Please help me to fix it

your design is very small with respect to the wavelenght. You should increase the mesh (mesh properties -> mesh per wavelength and mesh ratio limit).

Hi
Your frequency range simulation is low frequency and you need to use low frequency regime in CST (EM CST).

I appreciate your help.it works now. but the only problem is that, when I want to see the arrows of electric field, there are just two arrows. I changed the scale but it did not work.
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I also used EM CST but it was not suitable in my case. that's why I changed it