Costco's transition from American Express to Visa is drawing complaints from customers.
On Monday, Costco ended its 17-year exclusive partnership with American Express.
Social media is filled with customer complaints.
Many say their new Costco-branded Citigroup Visas have not arrived. Others report problems activating or using their cards or accessing their accounts.
Costco has not commented.
Citigroup says it's received 1.5 million complaints.
Costco customers complain about card switch to Visa from American Express