There's a huge discrepancy between what is available for Alexa for US users versus what is available for those in the UK. This has caused confusion and a lot of complain for Alexa device owners in the UK, but Amazon is beginning to sort out the differences.

According to an email circulating to developers, Amazon is planning to migrated all US-based Alexa skills to the UK skill database starting on Thursday, February 16, 2017 at 8:00 am.

FAQ available here: Alexa Skills English (UK) Migration FAQ