Situation:
The store switched payment providers from Cayan to Auth.net.
The store decided NOT TO do the Token transfer. They will manually re-enter credit card details in the store's customer profiles.

After setting up the gateway credentials, the store can charge a credit card in pickup and pay by clicking the auth.net payment option and manually enter the card details.,

..BUT the store can NOT save credit cards.
The alert is something like this:

and there is an error in Dev Tools that somehow points to a 'token'

Solution:

When a customer changes a payment provider for its gateway and DOES NOT DO a token transfer, we (from the support team ) need to hit the Delete All Merchant Ids button before, on , or after setting up the gateway.
This will, in effect, do the need to reset all the stored payment ids.

When a store does the token transfer, the support team does not need to hit the 'Delete All Merchants Ids' button.
The Dev Team will do it.

Here's a note from our Dev Team
Quote:

The DELETE ALL button should be done during the token transfer

The steps are like this...

1. Customer requests token transfer from losing processor

2. Customer receives new and old token list from gaining processor

3. Customer sends token list to Dark support

4. Dark support opens ticket with Dark dev to load new tokens

5. Dark dev loads new tokens and resets old tokens

6. Done!

IMPORTANT: following these steps the DELETE ALL button is never used by anyone but dev when they load the new tokens.