...
Open every duplicate rule in the list that is “Active” and is for “Lead” or “Contact” or “Account” object.
...
Make sure “Action On Edit” is set to “Allow” and the “Alert” checkbox is unchecked.
Make sure “Action On Create” is set to “Allow” and the “Alert” checkbox is unchecked.
...
Option 2
Deactivate the dupe rule.
...