in metafields when you create URL metafield with sms not working as expected

[developer16]

example :- 
i create URL  list metafield 

tel:wxample
sms:example

when i get its value from app extension liquid file.

product.metafields.metafieldKey.metafieldValue its give me like `["tel:wxample","sms:example"]`

but when i get like this way product.metafields.metafieldKey.metafieldValue.value its give me error

{{ product.metafields.nameSpace.keyName | metafield_tag }} this also not work for sms

if i remove sms then its working both case.