I agree,
1 disconnect all load and charge,
2 disconnect battery monitor and wait 1 min (5 wires monitor)
Check that BT module connected to BMS.
3 reconnect battery monitor cable
4 Connect any form of charger (Volt must be cell upper limit x cells unit) ex: 4s lfp 12v (3.6 x 4) 14.4v
If...