Trying to get a new token (App-Dashboard -> Marketing API-> Tools) gives me a https://developers.facebook.com/products/marketing-api/xxx/async/access-token-generation/?elem_id=u_0_v_Nl 500 (Internal Server Error)

for all our Apps. Worked last week, what is wrong?

Also access to the api via our existing token gives us {"error":{"message":"Error validating access token: The session has been invalidated because the user changed their password or Facebook has changed the session for security reasons.","type":"OAuthException","code":190,"error_subcode":460,"fbtrace_id":"AWg8rS652yn6zyLeD8eOWim"}}