You will find this setting at Dashboard -> Support -> Settings ->Term & Conditions & GDPR. Below are settings available:
This setting will allow you to enable or disable GDPR condition in create ticket page. If set enable, it will show text on page set in GDPR setting.
We refer Name and Email Address as personal data by default and for custom field, there is option given to set field as it is personal data or not. e.g. If you create custom field, Telephone Number to accept telephone number from create ticket form, it should be marked as personal data.
If personal data retention is enable, it will set time for which personal data should be retained in Days or Months or Year. For example, if you create a ticket with name test and email as email@example.com for which personal data retention is set for 1 month. After 1 month this name and email will be replaced by Anonymous and firstname.lastname@example.org. Also, you will be not able to search no of tickets created by this name.
If automatic personal data retention is not enabled, you can do it from delete personal data request feature given in default WordPress for particular user upon request.
We understand ticket data is important for us so we do not delete all ticket data. Instead we replace only personal data with anonymous.