Retrieve SharePoint Online list data - v2.0 connector is returning less than 1% of data

I have a Power BI report that queries a large SharePoint Online list (+40,000 items). This has been working fine until recently. It is now only returning 124 items.

However if I set up a new query and use the v1.0 SharePoint Online connector, it returns all my data.

I'm using the same account to access the list in both cases. The query is basic - return all rows, all fields from the list. Is there any reason why the v.20 connector would start returning far less items?

I've tried creating a new PBIX file, or restricting the query to only return the fields in the default view, but I get the same results.