OCI Vault Decrypt API giving 400 Bad request error

Summary:

Need to decrypt a file that comes as encrypted from the source system with public key. I have wrapped a private PEM key as a master encryption key in the OCI vault.

1. Whether using the decrypt endpoint works as the correct approach to get the file decrypted?

2. If yes, I am getting an error calling the decrypt endpoint from OIC as:

"x-content-sha256 x-content-sha256 was not passed in". Could you suggest a working payload?

3. If no, what is the correct approach to get this working?

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