APIs & Integrations


Merging contacts not possible



Our company has created a third party hubspot app and it is used by our customers to enrich their contact data with data from our system and other data that we collect.


We try to match a contact based on information from our system and if we can't find a contact, we create a new one in the hubspot account of our customers and add data from our system to it.


We also collect the hubspotutk cookie from the website visitors of our customer and we try to add data from that cookie to the contact the we have matched or created. 


We do this by finding the contact that is associated with the hubspotutk cookie and then we merge it with the contact that we have created or matched.


We use the following endpoints for the process that is described above:

  • /contacts/v1/contact/utk/{$utk}/profile
  • /contacts/v1/search/query'
  • /submissions/v3/integration/submit/{$portal_id}/{$form_guid}
  • /contacts/v1/contact/merge-vids/{$id}
  • /contacts/v1/contact (to create a new contact)


For one of our customers it seems that it is not possible to merge contacts. We keep gettiing the error following error: 'vid to merge is not a valid contact or is already in the process of being merged'.

Also here is a correlation ID for a request that got the above error response: '


Can someone help me to find out what the problem is?

1 Reply 1
Community Manager
Community Manager

Merging contacts not possible

Hey, @Manno 👋 This one is definitely challenging to diagnose. The correlation ID will be useful if your customer has access to support. 

  • Is this issue happening every time? Or is it intermittent?
  • Have you tried capturing a HAR file while triggering the error? Occasionally, HubSpot will dump more details, and we can capture them with a HAR file. HAR Analyzier

Other things to check:

  • Are these contacts in use by another system?
  • Are there already slight delays built in to help avoid any potential race conditions?

If this is only happening to one portal and not others, you may need to have them check if users, roles, or access to specific scopes have changes with that portal.





Jaycee Lewis

Developer Community Manager

Community | HubSpot