Due to a problem in Intel® Quartus® Prime Pro Edition Software version 18.1, you may see the error below during the Intel® Quartus® Prime Pro Edition Software compilation process. This problem occurs because there is no pin location that has been assigned in the design. The Intel® Quartus® Prime Pro Edition Software Compiler's Fitter attempts to place the pins into a 3V I/O Bank which does not support OCT with calibration.
Error(14566): The Fitter cannot place 1 periphery component(s) due to conflicts with existing constraints (1 pin(s)). Fix the errors described in the submessages, and then rerun the Fitter. The Intel FPGA Knowledge Database may also contain articles with information on how to resolve this periphery placement failure. Review the errors and then visit the Knowledge Database at https://www.altera.com/support/support-resources/knowledge-base/search.html and search for this specific error message number.
To work around this problem in Intel® Quartus® Prime Pro Edition Software version 18.1, manually assign the pins to any of the LVDS I/O banks which support OCT with calibration.
This problem is fixed starting with the Intel® Quartus® Prime Pro Edition Software version 19.1.