409 response for endpoint: PUT /v2/contacts/{contactId}

0 Votes

When trying to update a contact, I'm seeing a 409 response with this body (please excuse the escaping):


"[{\"error_key\":\"http.status.conflict\",\"error_message\":\"There was a conflict between the supplied data and the existing resource.\"}]"


The only change to the contact is that they are being added to a new list. During debugging, I noticed that this response also happens even if there are no changes to the contact at all.


Here is some info about the contact I'm having trouble with ([REDACTED] is by me):




=> #<ConstantContact::Components::Contact:0x000055e17e578400 @id="[REDACTED]",
@status="ACTIVE", @fax="",
@id="[REDACTED]", @line1="", @line2="", @line3="",
@city="[REDACTED]", @address_type="PERSONAL", @state_code="OH", @state="Ohio",
@country_code="us", @postal_code="OH", @sub_postal_code="">], @notes=[],
@id="[REDACTED]", @status="ACTIVE">,
#<ConstantContact::Components::ContactList:0x000055e17fb6fa60 @id="[REDACTED]",
#<ConstantContact::Components::ContactList:0x000055e17fb6f9e8 @id="[REDACTED]",
@status="ACTIVE">], @source="API",
@id="[REDACTED]", @status="ACTIVE",
@email_address="[REDACTED]@gmail.com">], @prefix_name="",
@first_name="[REDACTED]", @middle_name="", @last_name="Steiner", @job_title="",
@company_name="", @home_phone="", @work_phone="", @cell_phone="",
@custom_fields=[], @created_date="2017-07-28T15:07:04.000Z",
@modified_date="2019-05-20T19:30:47.000Z", @source_details="[REDACTED]">



Other contacts seem to be working as expected, but this one has been retried many times, encountering the same problem.


The documentation doesn't mention a 409 response, so what does the response indicate, and is there any way to avoid it?

0 Votes



Thank you for reaching out to Constant Contact API Developer Support.


A 409 conflict usually comes up when you are trying to use something that is unique and already in use, such as an email address. Though I can't say for certain why you are seeing this on an individual update when making no changes at all.


Since it seems to only be this one contact, I'd like to get more detail about them. Please email us at webservices(at)constantcontact.com with your Constant Contact username, and the email address for this contact and we'll be happy to take a closer look.




David B.
Tier II API Support Engineer

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