Write a formal grievance letter that gets taken seriously

Help me write a formal grievance letter.

What happened: [each incident with dates]
What I've already tried: [informal chats, emails]
How it's affected me: [work, health]
Evidence: [emails, messages, witnesses]
What I want to happen: [outcome]
Our grievance policy says: [paste the key parts if you have it]

Ask me up to 3 short questions first if anything important is missing. Wait for my answers.

Then:
1. A clear grievance letter: that it's a formal grievance, each issue with facts and dates, how it's affected me, what I've tried, and the outcome I want.
2. A list of evidence to attach or mention.
3. A plan for the grievance meeting: key points, questions, and asking who can come with me (tell me to check Acas on this).
4. Remind me to keep copies and to read Acas's guidance (helpline 0300 123 1100, Mon–Fri 8am–6pm) on the grievance procedure.

This is help with wording and preparation, not legal advice; point me to Acas (helpline 0300 123 1100, Mon–Fri 8am–6pm) or GOV.UK for my rights, and to Citizens Advice or a union if I need someone on my side. Only use what I've told you, leave blanks for anything I haven't given, and don't invent facts, dates or results. UK English.

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