E-mail Jeanette or Freek directly. They are independent confidential advisors. They have a duty to maintain confidentiality of your e-mail address or telephone number and everything you send to them.
If you would prefer to call Jeanette or Freek directly or (if that’s not possible) leave a voicemail, call them directly.
You can also post them a letter. Send your letter to De Vertrouwenspersoon, Postbus 429, 8440 AK Heerenveen.