SMA transceiver issue with IBERT test


We had created a simple example project for IBERT Ultrascale GTY IP(vivado version 2021.2) and we are running IBERT test for Quad 226 Bank on XEM8320-AU25P Development Board.
We are doing external loop-back by connecting SFP cables to the SFP+ Modules(SFP1 and SF2) and SMA loopback is also done using SMA cables.
When we run the IBERT test we see that only link 1 and link 2 is up.There is no link displayed for link 3.
What could be the reason for this.
What is the default impedance of the Tx and Rx lines of all the transceivers present in this bank so that we can verify the same?
Could you please let us know us about the same at the earliest.

Thanks and Regards,
Deeksha N