100a BMS Not Working

I have a 600 watt solar system with a 4 cell 12v (14.6v max) 100ah Sinopoly lithium battery and a 2000 watt pure sine wave inverter.

I have tried two separate of the same 100a Battery Management Systems (picture below) and neither of them seem to control or alter the cells voltage-wise. The one cell will die before the others (at about 3v or so) and one of the other cells will overcharge long before the rest. When charging, after the overall battery voltage reaches about 13.6v the one cell with shoot up very very quickly until the overall voltage of the entire battery reaches the preset limit on my charge controller, sometimes leaving the one cell overcharged. The BMS seems to do nothing to even slow the overcharge and imbalance down and when I disconnected the BMS altogether, nothing seemed any different with the way the 4 cells operated while charging and discharging.

What is happening when the one cell is charging so quickly when it reaches about 3.4 volts (about 1 tenth of a volt every 10 seconds)?

Also, why isn't the BMS not doing anything to control the cells? I set it up per the attached diagram.

Thank you for any help you can give!

Sounds like the cells are not balanced. You should bottom balance your cells and then fully charge them. After balancing if the cells are still not charging and discharging at very similar voltages then the cells are mismatched and probably shouldn’t be in the same pack. Also when Lifepo4 cells reach there upper voltage range the voltage will change very quickly. The same applies to the bottom of the range. The BMS is not doing its job if it allows any cell to exceed 3.60+/- .05vdc.