`/.auth/login/aad/callback` fails with 401 after sucessfull login

I have auth setup and I understand that /.auth/* is supposed to handle both the outbound and the inbound callback. However I get a 401 on return for https://prototype.nkdagility.com/.auth/login/aad/callback

**To Reproduce**

Steps to reproduce the behaviour:
1. Go to https://prototype.nkdagility.com/.auth/login/aad/
2. Login
3. Return to https://prototype.nkdagility.com/.auth/login/aad/callback
4. 401

**URLs**

Site: https://prototype.nkdagility.com
Build: https://github.com/nkdAgility/NKDAgility.com/blob/main/.github/workflows/main.yaml
staticwebapp.config.json: https://github.com/nkdAgility/NKDAgility.com/blob/main/staticwebapp.config.json
GitRepo: https://github.com/nkdAgility/NKDAgility.com/

**Expected behavior**

I expected this to be handled and return to site with auth tokens present.

Any help would be appreciated.