Guilin Sun
Ansys Employee

Does the simulation end at 100%? I guess so. please use smaller autoshutoff min such as 1e-6 or smaller, and use much longer simulation time, say 1e8, and make sure the simulation terminates at less than 95% (you can check it in the log file). If it still has data larger than 1 when the simulation terminates at less than 90%, then reduce the autoshutoff min further.

Do not use higher mesh accuracy for initial test, as it needs more number of PML. In your case, I think you can simply use the Standard PML, with the proper number of layers to make sure the PML thickness is about half wavelength. Please use mesh accuracy 2, and use an override region in the coupling region.

Make the port size larger, as long as the mode is correct.

You can search this forum for more suggestions from other posts.