Attempting to get threat submission via Graph API

[alistairtr]

I am attemtping to pull the threats submitted by users - that are visible in https://security.microsoft.com/reportsubmission using the following documentation.

https://learn.microsoft.com/en-us/graph/api/security-emailthreatsubmission-list?view=graph-rest-beta&tabs=http

I can see multiple submissions via the UI on my browser however the API is returning a null value everytime. Anyone have an idea as to where I'm going wrong?