Issue returning in retail store

So i bought this phone on Nov 6, in person from Apple store (not order pickup), paid in full no carrier finance. I was informed at the time that will be within holiday return policy (up to January 8). Was using it, then Weeks later I bought another iPhone in purple color and decide I will return the gold one later. Days ago I went to same Apple store, to return iPhone gold. After they scan the receipt, employee says they getting a message that wont allow the return (pic attached). They said they dont know specifics, just that they cant process, and refer me to call Apple directly. They know return date is still valid.

I call Apple, they said theres no block to this phone serial number. And refer me back to store since this was a in-store order(not online).

So i feel im getting the run around with little info. Anyone had similar situation or insights what to check next?

I have attached pic of Apple store device showing the message after scanning receipt