Mdrun log file error Large VCM(group MEMB)

GROMACS version:2020-UNCHECKED
GROMACS modification: No

I was running a continuous heating simulation in a DPPC bilayer system, from 290 to 350 k temperature where the rate was 0.2k/5ns which is slow enough. During heating I did not get any such error. When cooling it back from 350 to 290 I am getting this error in the log file of simulation. i am attaching the cooling mdp file and the error part of the log file here. kindly suggest any fix.

In the heating one all other parameters were same in the mdp just temperature was 290 to 350 and here it is 350 to 290.

The simulation is still running