Yes the exact minimum payment or a larger amount must reach the account on or BEFORE the due date shown on the statement, so payments by post need to be sent 7 days prior to the due date, debit card payment 5 days prior to the due date, through your own banks services 5 days prior to due date, on line 5 days,
any payments made after those times will often no reach your account on the DUE DATE and the system automatically places a late payment marker even if the payments is in the creditors possesion.