ADG1406 in LFCSP_VQ package. It is analog mux. All channels except last on pin 1 are working. I have 4 ICs and on all four common signal does not propogate through on the last 15th channel. Any idea?

I am using ADG1406 in LFCSP_VQ package. It is analog mux. The first 15 channels are working fine but the last one with output on pin 1 in this package does not work. Signal does not propagate through. I have 4 ICs and all 4 vehave the same way.

Do you have any explanation of what is going on. I am using +12/GND for supply voltages.

Thank you