Booking.com — bill is not given by hotel or booking.com site

I had made a booking in fab hotel silver in in noida from 18-2-19 to 21-2-19. I duly checked in hotel & checked out on 21st feb. While checking out i paid charges due to me & asked for bill. I was told that it will be sent by email.

When i inquired about my bill from hotel later on, i was told that bill will be given to booking.com site only as they had booked the hotel. Other sites such as makemytrip never had such issues.

When i logged in booking.com site, i was surprised to see that my hotel booking has been cancelled. I sent complaint to them for sending me my bill but no answer. I submitted complaint in their system but again no response.

When i called them, they said bill will be sent to me by hotel itself.

I do not know now how can i get my bill for claiming reimbursement. Is such a simple thing so difficult or them? If so then what is the purpose of such web site?