Web.Contents Power Query Incremental Refresh Error

Thank you! I was actually a little confused how to put api-version in the query because of the hyphen.

The solution was acutally a little different from what you recommend. What I ended up doing was passing in the URL directly, not into a function. Now the function looks like

GetJson = (offssett) =>
            let Options = 
            [
                Headers=[ #"Authorization" = "Bearer " & Token ], 
                Query = 
                [
                    IncludeItems="true",
                    IncludeTransactions="true",
                    Limit="100",
                    Offset=offssett,
                    CreatedAfter= Text.From(RangeStart) 
                ]
            ],
                RawData = Web.Contents("https://eu.bill.dotyk.cloud/nua-barcelona/Orders?api-version=2020-06-01", Options),
                Json    = Json.Document(RawData)
            in  Json,
        
        Json = GetJson(BaseUrl, UrlPath),
        Value = Json[#"data"],

        GetPage = (offssett) =>
            let Json  = GetJson(Text.From(offssett)),
            TestUrl = if Json[#"paging"] <> null then Text.From(Json[#"paging"][#"next"]) else null,
                Value = Json[#"data"],
                response = if TestUrl <> null then List.Combine({Value, @GetPage(offssett + 100)}) else Value
            in  response, 

But now I'll also fix the api-version.