Hi there. 

In case of quitting after the payment of bond money, as far as my knowledge goes, the amount is never refunded but you can surely write NEET again as long as you fulfil the eligibility criteria for writing the examination.

For the relevant information regarding the eligibility criteria, kindly refer to the following link: 

https://www.google.co.in/amp/s/medicine.careers360.com/articles/neet-eligibility-criteria/amp

Wishing you luck!