Cryptocurrency Vault

Today in the app I had a message to say that I can replace my spare change GBP vault with a cryptocurrency vault.
I have now closed my GBP vault, but I cannot see how to create a cryptocurrency vault.

Any pointers on how to do this?

Add new Vault -> Name your Vault- >'How much you would like to save?-> here click currency, then Other, and select, e.g. BTC

That was what I had tried, but I don’t see BTC in the currency list.

Got through to support. Apparently, although I received a message saying I can have this facility, in fact I cannot.