Power flow did not converge and pandapower.diagnostic() did not work

[GuanningC]

Hello everyone! I constructed a 6-bus power system with both balanced and unbalanced 3-phase loads. When I was doing time series simulation with dynamic active power loads, I found that the power flow may not converge. I did some test focusing on one balanced 3-phase load. I tried to modify its active power while keeping all other quantities in the network unchanged. And finally I found that there is a range for this active power. Power flow will not converge if the active power on this load exceeds the upper or lower limit. But the change of the active power on that specific load will only influence a single line and I did not find anything odd on that line. I also tried diagnostic function and got nothing returned. Can anyone help? Thank you very much!