API key confusion for GSA/SAM rest api

[Corey Foulds]

I have just received an API key from api.data.gov and it is not working for the following endpoints https://open.gsa.gov/api/entity-api/

I have also tried registering for an api key directly via https://api.sam.gov/signup/ and that page is blank.

I have creates a GSA account and a SAM account and nothing seems to work. Help on this matter would be much appreciated. 

To be clear, I need an api key that will work for endpoints like: https://api.sam.gov/entity-information/v1/entities?api_key= < value >