One customer, many channels: how a system knows the DM and the text are the same person
Identity resolution for a small business, in plain terms: what can be matched automatically, what needs the customer's help, how to merge safely, and what to do when the system is not sure.
Frontiva · · 4 min read
A system knows the Instagram DM and the text message are the same person by matching identifiers it can trust: a phone number given in the DM, an email used on both, a name plus a booking reference. When there is no shared identifier, it cannot know, and the honest design is to ask ("What is the best mobile number for you?") rather than guess. Merging two records is easy; un-merging two people who were wrongly combined is not, so the system should be confident before it merges and should keep a record of every merge.
What each channel gives you
SMS: a phone number. The strongest identifier for a service business.
Email: an email address. Strong, and often on the same record as the phone.
Instagram, Messenger: a platform account ID and a display name. The ID is unique to the platform; the name is not unique to anyone.
WhatsApp: a phone number, which is why WhatsApp conversations match to SMS records well.
Web chat: nothing, until the visitor gives something.
Matching that can be automatic
The same phone number on SMS and WhatsApp. A phone number typed into a DM or web chat that matches a record. An email on a web form that matches. A booking reference. These are exact matches on identifiers the customer supplied, and the system can link them confidently.
Matching that needs the customer
A DM from "Maria G" when you have three Marias. A web chat visitor who has not said who they are. A Messenger account whose name does not match anything. The right move is to ask for a phone number or email in the conversation, for a reason the customer accepts (confirmation, reminders, so a person can reply). Once given, the match is exact.
What not to do
Match on name alone. Match on a partial phone number. Assume the Instagram account with the same first name as a booking is the same person. Merge automatically on anything less than an identifier the customer gave. The cost of a wrong merge is showing one customer another customer's appointments, which is a privacy failure, not a tidiness problem.
Merging safely
When a match is found after conversations already exist on two records, merge the records: one customer, all conversations, all bookings, all consents (kept per channel and purpose). Keep a log of the merge with what was combined and when, and make it reversible by a person. Show the merged history in order, with the channel marked on each message.
When the system is not sure
Show the possible match to the person handling the conversation ("This might be Maria Gomez, 555 0100. Same person?") and let them confirm. A one-click confirmation from someone who can see the context is far safer than an automatic merge, and it takes two seconds.
Consent travels carefully
Consent to text does not become consent to WhatsApp, and marketing consent on one channel is not marketing consent on another. When records merge, the consents stay attached to the channel and purpose they were given for. The system should refuse to send on a channel with no consent even after a merge.
Frequently asked questions
What if a customer uses two phone numbers?
Both can live on one record, each with its own consent. The system asks which to use for reminders.
What about family members on one number?
A shared number is one record with a note, or several people with the same number and a person deciding which conversation is whose. Systems that force one person per number get this wrong; ask how yours handles it.
Can I see how a record was built?
You should be able to: which identifiers came from where, and every merge. If you cannot, wrong merges are invisible.
What Frontiva does here
Frontiva's CRM resolves the same phone number on SMS and WhatsApp to one contact automatically, keeps each channel as its own thread on that contact's timeline, and flags possible duplicates for a person to merge with one click. A STOP is recorded against the number, so it covers every thread. The unified inbox shows the threads. See deduplicating customer records.