LTI 1.3 connection to External Tool cannot create Lineitem

Hello,

I am running Moodle 4.1 and trying to configure Turnitin as an external tool using LTI 1.3.  Everything seems to be configured correctly.  The handshake between Turnitin and my Moodle site worked, but when I try to create an assignment I get an error from Turnitin "Unable to create lineitem container".

I checked the http request and I'm getting the following:

HTTP/2 401 
server: nginx
date: Tue, 01 Aug 2023 15:29:50 GMT
content-type: application/json; charset=utf-8
x-httpd: 1
host-header: 8441280b0c35cbc1147f8ba998a563a7
x-proxy-cache-info: DT:1

{
    "status": 401,
    "reason": "Unauthorized",
    "request": {
        "method": "POST",
        "url": "/mod/lti/services.php/2/lineitems?type_id=6",
        "accept": "*/*",
        "contentType": "application/vnd.ims.lis.v2.lineitem+json"
    }
}

In the tool configuration I have given the tool permission to manage grades and columns and accept grades from the tool.  I just can't seem to figure out what the problem is.  Any ideas?

Brian Tittl