Problems with a Rat Race (0.75GHz) on CST

I have some problems with the design of a Rat Race Coupler working at 0.75 GHz. i implemented it on CST but it does't work correctly.
data, figure and results are below.
Thank you for everuthing. i can also send the file.

As you can see, there is something wrong at port 2, so that you get total reflection. Check your model for open circuit or short circuit at port 2.

How could i check my model for open circuit or short circuit at port 2? what should i do? I'm sorry but I'm a beginner.

Make sure your ground plane is not touching your top traces.
I'll give it a look if you upload your model.