Gonduir

Unfortunately the seplos BMS doesn't balance as quick as an active balancer like @WannabeSolarSparky has installed. When it goes into balancing at +95% it does a few different things... it limits the current to 10A, but it also does what is called 'intermittent charging' where the battery actually switches between charging, discharging and standby constantly every few seconds while it burns off charge in the highest cells, so it takes much longer to balance. This behavior also drops the current to zero every time the battery goes into standby which the inverter can mistake as the end of the charge cycle. Balancing might be quicker than 120mins, I just use that to be sure in case of bad weather (I'm off grid) because once the battery reaches 100% it disconnects the cells from the DC bus anyway and the cells will settle, so they won't sit at bulk voltage the whole time.
 
There was a known batch of batteries which had a bad diode installed due to the covid shortages (I think in the BMS), but afaik they were being fixed under warranty without any questions.
As @Coulombmentioned above this is the equalization setting, you need to change the 'timed absorb' to 120mins (you can change this later once you've seen how long it actually takes to balance your battery)
The seplos BMS will only start balancing cells above 3.5V, so some cells need to get that high. Also, if you don't charge to 100% fairly regularly you can start to get SOC drift.