I can't book the same room but different dates?

Why I can’t book the same room but different dates?For example, I booked a deluxe double room from 2019.02.01-2019.02.02, then I continued to book the same room, but it was 2019.02.03-2019.02.04. In my shopping cart, it will only keep My second reservation, two deleted my first reservation.Please correct this problem, there are many guests who will make such a reservation like me.