Rust on brand new earrings !

My boyfriend bought a pair of sterling silver earrings and a bracelet online for me. He went to collect and opened the parcel in Somerset West store and the earrings had rust on them LITERAL rust as if it’s not brand new. The ladies in the store told him he cannot exchange or refund due to the policy they can have it cleaned, even though the earrings never even left the store! Second time around having ****ty experience with sterns earring. Really disappointed!