Inter depository delivery -sharekhan

can anyone from zerodha clarify on this thing= i had an old account in sharekhan which i was not using and it had some shares [10quantity]some unlisted. i had read that when you close account the sharetransfer is done free. so i had submitted the cmr physical copy obtained from zerodha to sharekhan and paid them about 1000rs which they asked for demat bill.
Q1= [althought i closed account on 10dec2020, they have took charge till march2021], is it right?
q2= i received sms of share transfer to zerodha on 31dec2020, but today in my emai i receved bill from sharekhan for 400rs, citing “inter depository delivery”. when i closed account ,should not the transfer be free.
please clarify