I don't think its a scam as they have a physical shop, you can see it on google maps and they have reviews as recent as two months ago, so I am guessing they are just a little lax at answering the phone. Looks like they are also a coffee shop which is popular and uses the same phone number so perhaps they just are not answering. Try contacting them through facebook
www.facebook.com/BoardCultureSurfShop/