Ethernet LEDs won't turn off when i unplug the Ethernet cable
Not enough information. What you describe is not normal, and can be a cause of various issues:


issues with software configuring chip working in wrong mode (e.g. external PHY mode);
issues with hardware like you using wrong transfomer (e.g. non-symmetrical one), slightly wrong values for RX/TX pull-ups.


Please refer to reference design to ensure you have correct circuit, and parts you use are correct for the chip. Reviewing application notes would also may help.

If you still have issues, detail your question with circuit diagram and software settings, or apply directly to the Microchip support.