I'm currently having issues trying to use the integrated Making Tax Digital facilities on Dynamics 365 (otherwise known as NAV 2019)
I have setup the GovTalk Service on Service connector (see below) and as far as I am aware there is no issue with it.
![81bz5buv8rgy.png](https://us.v-cdn.net/5022383/uploads/editor/6j/81bz5buv8rgy.png)
However I cannot run "Request Authentication Code" HMRC VAT Sandbox as it gives me the following message, {"error":"invalid_request","error_description":"client_id is invalid"} , please see below for the HMRC VAT Sandbox Page.