Hi,
DPC is "Delay Pay Charges." It has nothing to do with your Dmat a/c. It is charged @ 24% on the shortage in your trading account going in minus balance.
If you are careful with your ledger daily balance, then this charge will not appear.
The ledger balance that you are able to see is not the real ledger that they follow. For example, you sell equity worth 50,000, the balance in your ledger is updated on the same day, but in the real ledger the same is credited on T+2 days. So, if you use that 50,000 either by withdrawal or buying something else on the day of T day, then 2 days DPC will be charged. You need to be aware of this aspect. I did learn the hard way.
Cheers.