lipo cell and balancing tab problem

[tols]

I have a weid problem for my 8000mah 2s2p lipo. When I connect lipos hyperion balancer tab to my hyperion eos 0610 duo charger it says that one cell has 2.86V and the othes has 3.83V power.
If connect the charging cable then cells raises up to 4.1V.
If I change the balancer board and connect lipo hyperion female to jst-xh male adapter then both cells has 3.83V. I've tried another balancer also and that works exactly same.
Does anybody know what could cause this problem?