Why am I not able to place an F&O order on the monthly expiry day?

As per our physical settlement policy, we will be blocking the contracts mentioned:

InstrumentExpiry TypeStatus
FuturesIn every current month expiry dayAllowed
FuturesIn every current month expiry dayOvernightOnly square off allowed.
Fresh order blocked
OptionsIn every current month expiry dayIntradayFresh order blocked
OptionsIn every current month expiry dayOvernightOnly square off allowed.
Fresh order blocked