I am pretty new to cryptography.
Recently I run into this question where I have two different public keys with the same private key, and I need them for fully homomorphic encryption.
Let's say messages from party $A$ and party $B$ are encrypted by two different keys and FHE operations are performed on the encrypted messages. Party $C$ has the one private key to decrypt it. The two different public keys are generated using Party $C$'s public key via Key Reencryption.
How do I perform the FHE operations on these two messages encrypted by different public keys?
P.S. I am using the Palisade library to implement my idea. A little suggestion on how to implement this on Palisade would also be really appreciated.