Hi @M2U
As per SEBI guidelines, Exchanges and respective clearing corporation (CC’s) have implemented Peak margin in phrased manner i.e., Dec 2020 to Sept 2021 to go fully live on peak margin (More details: Peak margin requirements from Dec 1st 2020 & its effects).
Before the peak margin introduction, there was no restrictions on intraday leverage offered across segments by brokers, no criteria of broker- baring the penalty, etc. (Can find the info here: https://www1.nseindia.com/products/content/derivatives/equities/penalties.htm).
After October 11th 2021, the upfront margin shortfall i.e., short collection of SPAN + Exposure margin due to any reasons during the intraday as well as for EOD has to be borne by broker. Circular reference : https://archives.nseindia.com/content/circulars/INSP53525.pdf
In your case, you mentioned the penalty as on 21.09.2021 which is before this guidelines come into effect which has to be borne by client and we had refunded the upfront margin shortfall penalty post October 11th, 2021. Also, we completely stop passing the upfront penalty from August 2022.