I have ordered quite a few batteries from them and every now and then I will get one that does that. Usually I just put in on the charger using the NiMh setting for about 1-2 minutes and that brings the voltage up enough to allow the charger to read the correct cell voltages to go ahead and charge and balance it on the LiPo setting.
Try this and see if it works. If not, I have had good luck in contacting them to resolve a few small issues.