You may receive above error message when select the port number greater than 8 and transceiver type as LVDS I/O for Triple Speed Ethernet IP Core in Quartus® Prime version 17.0.2 including patch 2.05 or Quartus® Prime version 17.1.
Device Family: Intel® Arria® 10, Intel® Cyclone® 10 GX, Intel® Stratix® 10
Area: Intellectual Property
The Triple Speed Ethernet IP with LVDS I/O interface can only support up to 8 ports. Therefore, port number larger than 8 is not a valid option and those options will be removed in a future version of Quartus® Prime.