When filters are used, the Power BI REST API returns an “Internal Server” error, instead of the data we are requesting. Even in cases when the REST API doesn’t fail, using filters significantly slows down the response from the server. When customer data is sufficiently large, the processing on Microsoft side is slowed down so much, that it exceeds some kind of their internal timeout, and an error is returned. We know Microsoft has released new Power BI APIs, but we need time to switch to them. In the meantime, it is important that the filter works again.