What can I do if my in-laws are threatening me with false dowry charge

Sir, I am a govt. Servant and married in April 2022. My wife and I had good terms. But she died on 19th of June in 2023, due to critical medical condition lungs failure. During her treatment. We have medical documents of hospital. Now after the death of my wife(only child), father and mother of hers are threatening me of lodging case against me regarding the dowry case and return of items received in wedding. They have bank statement of transferring money to my bank account. The money they gave me take return in form of jewelry. Wife was in job. So she resides at her father's home. I was posted in M.P. Now what should i do in this regard.