"We can't approve this," the Finance guys wrote.  "These prices are much higher than what we've been paying.  Where did you get these prices?  Explain!"

"I received these from the supply chain," I wrote politely back.  "Supply chain, can you tell Finance where you got these prices?"

"Finance provided us with those prices," Supply chain replied.

So there you go, Finance.  Go talk to yourself, or, as you seem unwilling to talk to yourself, you can go do other things to yourself.