Social media users have complained of long waiting times on the My Health Record hotline and a temporary breakdown in the single sign-on capability of the MyGov site on the first day of the three-month opt out period.

Twitter users who tried to opt out have reported receiving messages that the call centre was experiencing a high volume of calls and others have had problems verifying their identity in order to opt out online.

A spokesperson for the Australian Digital Health Agency said if consumers were not able to get through today, they can opt out over the next three months. The opt-out period ends on October 15, but consumers can still opt out or in at any time.