This happened with me when using Coin from Zerodha..And due to their mistake i had to miss 1 installment INSPITE of having sufficient funds in my account. I had to rigorously follow it up with them as they dont seem to be too concerned regarding it..I have everything on email...Even after requesting them to revert if the required KYC documents are available with them they were lazy in responding back. Fortunately the thing has got resolved and back on Coin