Dear Ruchi,
We had almost same issue recently with SIXT! And they are claiming full amount of 7k Euros, even though we purchased full coverage insurance !
I happen to find your story by checking similar issues to other clients and i would appreciate any advice, as we got a short deadline to pay and only after 3+ months from returning the car and filling the report etc
the car has only minor scratchs so we find it extreme amount.
the reason is same as in your case which is" not calling the police"
i would really appreciate any information you can provide regarding how you dealt with it ! And if there is any chance i can pay less or negotiate.
Best,
kiki

kkiki, this post is 3-1/2 years old and was the OP's only post, so it's extremely unlikely that he will see your question.

I'm facing a similar issue with Sixt reaching out to me 8 months after the incident.

kkiki Please share your experience handling this claim. What is your advice?

You are unlikely to get a response from a one time poster who posted 3 1/2 years ago.