Booking.com Flight Booking Confirmation Missing

I booked a flight through Booking.com on 26 September from Mumbai, paying a total of 200 USD in cash. Although the amount has been paid, I have still not received any booking confirmation email or receipt, even though I was given the booking number 8554908***. Because there is no confirmation or ticket information, I am unable to be sure that my flight is actually booked, and this is causing serious uncertainty for my travel plans. I tried to reach Booking.com customer service by phone but could not get any effective assistance or resolution. I request that my reservation be urgently located using my booking number, that my official booking confirmation and receipt be sent to me as soon as possible, or, if the booking was not completed, that I be clearly informed and my payment situation be clarified.