Who pays for delivery when the shop sent the wrong goods?

Markied

Can anyone let me know my rights ? I bought my girlfriend a bed frame mattress and headboard in Stockport . As she lives in the Isle of Man she paid for the delivery seperately through a courier firm. The bed arrived and the shop sent her the wrong more expensive bed. She rang them and they said if you accept the wrong bed we will give you £50 but we won’t pay for the return of the wrong one and it’s replacement. She agreed . I’ve now discovered they’ve sent the wrong head board that doesn’t fit and 4 casters were missing . We want them to send the correct headboard and 4 casters and take the wrong head board back.
What are my rights as they said they won’t pay for the delivery costs?
Thanks

baza52

She rang them and they said if you accept the wrong bed we will give you £50 but we won’t pay for the return of the wrong one and it’s replacement. She agreed

Ask her to use to £50 to buy a new headboard. Im guessing she was keen to take the £50 offer as she accepted it.