Write Customer Complaint Response Scripts

Write response scripts for handling customer complaints in the following context:

Business type: [e.g. SaaS / e-commerce / hospitality / financial services]
Support channel: [email / live chat / phone / social media DM]
Brand tone: [warm and human / professional / direct]

Write response scripts for the following complaint scenarios:

1. Product doesn't work as expected (bug confirmed):
   - Acknowledge, apologise, explain what happened, timeline for fix, interim workaround

2. Product doesn't work (user error — but they don't know that):
   - Correct without making them feel stupid

3. Billing error (charge that shouldn't have occurred):
   - Apologise, confirm refund timeline, reassure

4. Delayed delivery or fulfilment:
   - Proactive update and management of expectations

5. Escalated and angry customer threatening to leave:
   - De-escalation language and retention offer strategy

6. Public complaint on social media:
   - Public response to move to private channel + private resolution

For each script: include the exact language to use, what NOT to say, and the underlying principle.