I cannot get the API to return any response except for: ‘{"code":"invalid_credentials","message":"You have to be logged in to perform this action."}’

My curl command (where {api-key} is my hard-coded API Key found in my profile settings): curl -v -u {api-key}:X -X GET 'https://domain.freshdesk.com/api/v2/tickets' -H "Content-Type: application/json"

Do I keep getting this message because I’m on a free trial version of Freshservice