If you are struggling to log into your Defence Gateway account, your first step is to reset your details.
Use the links on the Defence Gateway sign in page:

If you need to update or reset your Defence Gateway Two Factor Authentication (2FA) method please contact the Helpdesk to request this.
If you still cannot log in after attempting to reset, this may mean your Defence Gateway account or Westminster record is not set up correctly. In the first instance, please contact your County/ JMC/ HQ administrator and ask them to check your account details are correct in Westminster and JPA.
If you have tried too many times to log in, your account will lock. Contact the Helpdesk to get your log in attempts reset.