I am facing a recurring issue with my Shopify store where returning customers are unable to complete a second purchase. When they reach the checkout page, they receive the following error message:
“Contact info must match the account you’re signed in to”
Details of the issue:
Scenario: The customer has ordered from us before and their details are already in our system.
The Conflict: Even though they are using the same email/phone number as their previous order, the system blocks them.
Environment: This is happening frequently when customers access the store via the WhatsApp in-app browser.
App Context: We are using an integration that seems to be related to cranberry.fit / WhatsApp ordering.
What I’ve checked:
The customer’s email and phone number in the Shopify Admin match what they are entering.
The error persists even if the customer tries to re-type their information.
My Questions:
Is this caused by a “Multipass” issue or a session conflict within the in-app browser?
How can I allow customers to checkout without the system forcing a strict session match that blocks the order?
Is there a setting in “Customer Accounts” (New vs. Classic) that might be causing this?
I’ve attached a screenshot of the error for reference. Any help from the community or Shopify experts would be greatly appreciated!
This issue usually happens because of a session or login conflict in the WhatsApp in-app browser. When a customer opens your Shopify checkout through WhatsApp, it may carry an old or already logged-in session, sometimes coming from the cranberry.fit integration. If the customer then enters different contact details at checkout, Shopify detects a mismatch and blocks it for security, which shows the error “Contact info must match the account you’re signed in to.”
This is more common in in-app browsers because they don’t handle cookies and sessions properly. They can keep old login data or reuse a previous session, which creates this conflict.
To answer your questions clearly:
1. Is it Multipass or an in-app browser issue?
It’s mostly both. The WhatsApp browser is the main trigger, but if cranberry.fit is using Multipass, it may auto-login the customer with a specific email. Then WhatsApp keeps that session, and when the customer tries to use different details, Shopify blocks it.
2. How to allow checkout without this issue?
You can enable guest checkout so customers are not forced to use a logged-in account. Also, ask the cranberry.fit team not to pass a pre-logged-in session when opening checkout from WhatsApp, or to always send a fresh session. Another option is to add a logout step before redirecting to checkout. You should also test checkout using a normal browser (like Chrome or Safari) or a direct checkout link without cranberry.fit to confirm the root cause.
3. Does New vs Classic Customer Accounts matter?
Yes, it matters a lot. Legacy (classic) accounts use Multipass, which can cause this issue. New Customer Accounts use a more secure system and can reduce this problem. But before switching, you must confirm that cranberry.fit supports the new system, otherwise their WhatsApp flow may break.
In short, the quickest fix is to enable guest checkout and talk to cranberry.fit about how they handle sessions in WhatsApp. The long-term fix is to move to new customer accounts if their integration supports it.
