Some FreshChat Users created through WhatsApp don't have a phone field

Hi all!

I’m working with a FreshSales Suite installation where leads are primarily contacting the business through WhatsApp.

I’m trying to look up FreshChat Users via API, then update a custom field. Step 1 is to look them up by phone number through the API. I’m using the list users by specified criteria method documented here: https://developers.freshchat.com/api/#list_users. In all the scenarios I’m looking at, the User exists because of a conversation initiated by the lead through WhatsApp.

I’ve noticed that sometimes I don’t get any results. When I manually find the User ID in the UI and fetch the User by ID through the API, the User exists but there is no phone field present in the payload.

Could you help me understand why we would have a FreshChat User without a phone field if that User contacted the business through WhatsApp? Most Users have this automatically set, and I don’t see a pattern in the ones where it is missing. Note that in the conversation sidebar UI, the phone number is always visible in the “Main Phone Number” field, even in the ones where phone is missing in the API (though this seems to be showing the FreshDesk Contact, not the FreshChat User)