Ansys HFSS : Failed to solve port 1, solving at too low frequency is a possible cause

Hi there,

I am trying for days to simulate a simple antenna design with Ansys HFSS and I am always getting this error message:
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Ansys_MapleWireless5300_2 (C:/temp/Ansys_MapleWireless5300_2/)
HFSSDesign1 (DrivenModal)
[error] Solving adaptive frequency ..., process hf3d error: Failed to solve port 1, solving at too low frequency is a possible cause. Please contact ANSYS technical support. (7:58:28 Feb 13, 2020)
[error] Simulation completed with execution error on server: Local Machine. (7:58:49 Feb 13, 2020)
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Can someone please help me?
I don't get what I am doing wrong.... I have added an exitation and a pec element above it. But it keeps giving me these errors!
I am happy to share the project file!
It is a 5.3Ghz antenna!

Thanks for your help!
Cheers!
careyer!