Web.Contents failing to authenticate with Authorization string variable, only taking string

Hi Team,

I have come across this very strange problem where the ''Authorization' parameter in Web.Contents will fail authentication if using a variable (Shown below with variable token from another query).

I generate in Query 1 the bearer token required for authentication in Query 2, however when passing it into Query 2 the authentication fails.

Query1

generate_token= "Bearer XXXX"

Query2

the_access_token = generate_token

Source = Json.Document(Web.Contents("https://ABC.com", [RelativePath = "XYZ", Headers = [Authorization=the_access_token ]]))

However, running the below with the exact same string except not in parameter form works fine. 

Source = Json.Document(Web.Contents("https://ABC.com", [RelativePath = "/XYZ/", Headers = [Authorization="Bearer XXXX"]]))

Any ideas on why this may be?? There are no difference between these two strings.