AWS lambda function not processing POST variables

I have a lambda function which works correctly when I test in the AWS Lambda dashboard, however any json data I post to the function appears to be ignored.

If I test with curl:

curl -X POST -H "Content-Type: application/json" -d '{ "email":"email@.email.com", "fullname":"Mr Tester", "address":"1 Street" }' https://API.Gateway.url

In the lambda function code using

exports.handler = function(event, context, callback) {..}

event.email is always null.

via VeloursRouge