Morning Peggy
Welcome to the Forum
🤣🤣🤣 BMW Dealers have a twisted sense of humour don't they 🤣 Then they will tell you you should have a pair
Take a look at www.realoem.com it is a BMW online parts list (same as the Dealers use) put the last 7 digits of your Vin number into the search box it will call up your model search the Light section for the part number for the Headlamp.
Once you have it carry out an internet search you should find a replacement for about £200 upwards depending on source, any sensible home mechanic will be capable of changing them over
Dave