Needs some help with RelativePath when using a Headers =[]

I have the following source section of my query, which runs fine, but I'm trying to use RelativePath methodology so I can set up automatic refreshes in PBI service

let
    Source = (page as text) as table =>
let
    Source = Json.Document(Web.Contents("https://api.harvestapp.com/v2/invoices?per_page=2000&page="&(page), [Headers=[Authorization="**mykey**", #"Harvest-Account-Id"="******", #"User-Agent"="****"]])),
    #"Converted to Table" = Table.FromRecords({Source}),

But the various resources I used when trying to use the relative path method didn't show any examples that also have a headers section like mine does. I assume I can probably rework my headers section, but i'm not sure where to start, this is what i ended up with after trying some tutorials, but I get errors that too many arguments are being passed into the function

let
    Source = (page as text) as table =>
let
    Source = Json.Document(Web.Contents("https://api.harvestapp.com/v2/invoices",
    [RelativePath ="?per_page=2000",
    Query = [page=(page)]], 
[Headers=[Authorization="**mykey**", #"Harvest-Account-Id"="******", #"User-Agent"="****"]])),
    #"Converted to Table" = Table.FromRecords({Source}),

I tried a few different variations similar to this, like moving the per_page into the query section, and the like, but i get the same error, that too many parameters are passed. Any ideas or resources that will move me forward are greatly appreciated