Subject access request
Anyone can make one, in any form, to anyone in the organisation. There is no prescribed wording and no requirement to use a form.
The response is due within one month, extendable by two further months for complex or numerous requests, and normally free of charge. A request made verbally to a volunteer counts, which is why everyone needs to know how to escalate one.
Requests often arrive in the middle of a complaint or dispute, which is exactly when process matters. The ICO helpline is free.