Help - LBA10 balancer

I'm currently doing a standalone balance on both my Maxamps 6000mah.

One is balancing with cell led1 quickly flashing (discharging that cell at low/medium rate)

The other lipo however was fully charged and when I connect it to the balancer the status led flashes twice meaning this is an error (battery voltage higher than expected).

Does this mean I have to discharge it a bit for the balancer to be able to do its work? Or is something wrong with that lipo?

How do I measure the voltage of each cell in a lipo ? Do I have to take it apart or do I measure it at the balancer plug ?