Dynamic Web.Contents Power BI Refresh Error

Hi aTChris 

there are several blog posts on how to work around this problem.

Web.Contents(), M Functions And Dataset Refresh Errors In Power BI

Dynamic Web.Contents() and Power BI Refresh Errors

Using The “Skip Test Connection” Option For Power BI Data Sources To Avoid Scheduled Refresh Failures

As for the syntax of the workaround, 

you could check this blog to learn more.

Revisiting Dynamic Web.Contents()

Based on my understanding, your code can be modified as below

(pagenumber as text) =>
let

Source = Json.Document(Web.Contents(
"https://xx.xxx.com/xx/xx/xx?size=1000&page=1",
[Query=[page=pagenumber]])),

You can create a query parameter called "pagenumber",

Power BI Desktop Query Parameters, Part 1

Best Regards
Maggie

Community Support Team _ Maggie Li
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