Zoom Car — damaged windscreen noticed after taking the handover of vehicle

First off all let me clarify that the details specified in the recovery note is wrong. The outstanding amount which according to me is wrongly charged is toward damage of vehicle and not towards use of vehicle in excess to the paid rent.
As I understand that these charges are towards damaged wind screen. Let me clarify that when I had handed over the vehicle at 4.15pm and till the time I got the booking closure confirmation which was at 4:35pm there was no damage. Even the representative who took over the vehicle had inspected the complete vehicle and asked for justification for few old damages which the vehicle had while I took the vehicle.I showed him necessary video and photograph which convinced and based on it the booking was completed at 4:35pm.
I don't understand that if the windscreen was damaged why it was not noticed in these 20minutes which the representative took for inspection and to take the handover of car from me. Windscreen as I understand is made from toughened glass so if there is any damage it is always clearly noticeable.
Later at 23.54 IST I get a message that the charges have exceeded and I have an outstanding to pay which is 1000 INR. On inquiry I find that the total amount charged is 6000INR which is towards windscreen damaged (Broken windscreen). Later in few hour this amount is 10000INR now. How & Why I don't know.
I would request you to give an explanation for why I should pay when the broken windscreen was not reported while taking the handover. In fact according to me this damage has happened after handover of vehicle by the person who has taken the handover and is transferring the blame to my account.
The only request I have to make is to reverse this charges and cancel the noticed generated.