I have a CSV with various fields, including Internal ID
and Phone
. I want to match Internal ID
to Contact ID
, and add Phone
to the set of phone numbers for each contact.
I use a simple field mapping for import, shown here (real data redacted for most fields):

But I get the following error:
When selecting the field mapping, there are 5 options with an asterisk *
by them, and Contact ID
is one of them (along with the other 4 First Name
, Last Name
, Email
, and External Identifier
), indicating (I presume) that they're valid for matching to a contact. Why is this not respected when actually doing the import?
And why does the preview say there are 459 "valid rows", when it should already know at this stage that it's not going to succeed?
I'm wondering if I need to create another dedupe rule for Contact ID
, maybe? Or if I'm matching on Contact ID
, maybe I don't need dedupe checking (set to "No Duplicate Checking"), is it a special case, maybe?
Any help is appreciated, thanks.