Our organizzation is running CiviCRM 4.6.8. We are setting up an event and participants can register online. while configuring the on-line registration page, we get the error:
Duplicate Matching Impossible The selected profiles do not contain the fields necessary to match registrations with existing contacts. This means all anonymous registrations will result in a new contact.
We have specified a custom profile to register participants. The profile includes as mandatory field, the ID number of the person as per their South African Identity document or passport. This field will allow us to uniquely identify each participant.
We have also created a custom dedupe rule (unsupervised) as follows: Field -> ID Number Length -> left this blank Weight -> 30 Weight Threshold to Consider Contacts 'Matching': 30
Why do we get this error and how can we resolve it? We need to ensure that a participant can register only once for this event, as it is a competition.