The error is not a bug—it is a safety mechanism. Your switch is protecting you from configuring an invalid physical layer state that could cause link flapping, CRC errors, or complete loss of communication.
Look for unrecognized vendor, temperature warnings, or missing EEPROM data. command failed port not compatible duplex mode
If output shows Duplex: Unknown or Half-duplex (default) , the port may be mis-sensing. The error is not a bug—it is a safety mechanism