Refund but lost voucher

Morning

 

i have an issue , I purchased an item used a £50 off voucher from eBay .  The item didn’t turn up or get posted etc after raising claim got refund money back but now I’ve lost my voucher .  Surely I should get this to use on another item ?  Is there an online chat or phone number I can speak to someone about this as feel unfair

 

thanks