Bearer Token Expires before GET Request Completes

I'm still struggling with this one. Looks like everytime the loop runs in the List.Generate(), the call to my custom GetToken() function is just regiving the loop the same token. I was hoping to get a new token on each loop so that I wouldn't run into the 30 min expiration that each token has. 

let
  Source = List.Generate(()=> [Result = fApi(0,endpoint,ext,accesstoken), offset=0, endpoint="staffs", ext="ed-fi", accesstoken = GetToken()],
		                        each not (Table.IsEmpty([Result])),
                                each [Result = fApi([offset], [endpoint], [ext], [accesstoken]), offset=[offset]+Number.FromText(LimitOffset), endpoint=[endpoint], ext=[ext], accesstoken = GetToken()],
                                each [accesstoken])
in
Source

(Offset as number, endpoint as text, ext as text, accesstoken as text)=>
let
    data = Json.Document(Web.Contents(baseUrl,
    [
        Headers = [#"Authorization"="Bearer "&accesstoken,#"Content-Type"="application/json"],
        RelativePath=relativePath&"/"&ext&"/"&endpoint,
        Query = [#"limit"=LimitOffset,#"offset"=Number.ToText(Offset)]
    ]
    )
    ),
    #"Converted to Table" = Table.FromList(data, Splitter.SplitByNothing(), null, null, ExtraValues.Error)
in
#"Converted to Table"

() => let
    token_url = tokenUrl,        
    body = "Client_id="&clientKey&"&Client_secret="&clientSecret&"&Grant_type="&grantType,
    Source = Json.Document(Web.Contents(token_url,
    [
        Headers = [#"Content-Type"="application/x-www-form-urlencoded"],
        Content = Text.ToBinary(body)
    ]
    )
    )
in
  Source[access_token]