Why am I getting `API Key not known`

Technical Issues
#1

If I try to use my token from https://my.opencellid.org/dashboard#accesstoken, I get:

$ curl --location 'https://opencellid.org/cell/get' --header 'Content-Type: application/json' --data '{ "token": "pk.XXXX", "radio": "lte", "mcc": 404, "mnc": 90, "cells": [{ "lac": 6101, "cid": 231254816, "psc": 241 }], "address": 1 }' 
<?xml version="1.0"?> 
<rsp stat="fail"><err info="API Key not known: " code="2"/></rsp>

Any ideas how to resolve?