Costco, Citibank, Visa, and all of the companies’ customers had plenty of notice that the warehouse club’s store-branded credit card would be switching from American Express to a Citi Visa card. The transition didn’t go very smoothly for some members, but everyone assumed that the transition-related problems would be over by now. Nope. Some customers received cancellation notices at the end of last week, and are now very confused.

As you may remember, Costco members took to social media to share their frustrations, since at times it was impossible to actually get through to Citi on the phone.

Frustrated members threatened to do the unthinkable and cancel their Costco memberships.

Customers complained that they hadn’t received their new cards, that they weren’t able to activate them, or that their Costco membership numbers weren’t connected to the new payment cards.

On Friday, customers discovered a new problem: they received letters telling them that their cards had been canceled. These e-mails were intended for people whose Costco memberships had lapsed, making them ineligible for the store card. That makes sense, but the problem is that Friday’s letter went to some of the wrong people. They were now rather confused people.

Business Insider checked with Citi, and the bank told them that this was an error: the company meant to purge people whose memberships had really lapsed, and instead people with accounts in good standing received them.

Since the e-mails were actually meant for other card holders, customers were concerned that there had been a data breach or other problem causing them to receive other customers’ e-mail.

In a statement to BI, Citi explained that the error only affected “a small percentage of Costco members,” and has now been resolved.

Costco might [heart] Visa, but its members seem a lot less thrilled about the transition.

Costco’s credit card nightmare just got even worse [Business Insider]

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