curl --request POST \
  --url https://api.hubapi.com/marketing/marketing-events/2026-03/{appId}/settings \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "eventDetailsUrl": "<string>"
}
'

{
  "appId": 123,
  "eventDetailsUrl": "<string>"
}