Warning 015: Net {net1} is terminated to termination reference net {net2} but also grouped differentially (via pin {pin1}) with net {net3}, which is not terminated to {net2}

Net net1 is terminated to termination reference net net2 but also grouped differentially (via pin pin1) with net net3, which is not terminated to net2

When a differential signal is terminated to a termination reference net, XJTAG expects that both positive and negative legs of the signal will be terminated to the same reference net.