Contact search query by phone number fails to return existing results



I'm currently working at on integrating Hubspot CRM with our product. What we do is fetching contacts using GET /contacts/v1/search/query and then creating engagements.
We do search using several format numbers and most of the time API can return one or more results. But we noticed that sometimes (when looking for US and AU numbers in our cases), even when searching with the exact number format as the one registered for the contact, the search query returns 200 OK with 0 contact found.

The odd thing is that, when we go on the CRM and search for contacts using "Phone Number" and "contains exactly" with the same value, it finds the result!

Would you have any details or ideas on why this search would fail to find contacts when looking for strict matching of phone numbers?
If necessary, I would be able to give you extra information with the exact queries we do and screenshots of the CRM.

Thank you in advance for help,


Hi @FlorianM,

Can you send me a link to a specific contact record that isn't appearing in the search results, as well as the query you're making where you would expect to see that contact?