how to stop overwriting output file of concentration everytime

Hey everyone,

I set to monitor chemical concentrations for two specific elements in solute.inp. Like this:

Writing control variables [7i5]: 
    1    2    2    4    0    1    1    ! NWTI,NWNOD,NWCOM,NWMIN,IWCOMT,iconflag(=1:mol/l),minflag(=1 for volume fracsince t=0)
Elements to monitor (element code names) [xa5]:
 1120 1125 

Actually, it does output concentrations for these two elements in a certain txt file. However, this output file was overwritten every timestep. I couldn't get data of concentration over time; Only the data of last step would remain. Why does it overwrite? Did I misunderstand something?

Any suggestion is mostly welcome!