The Walmart’s U.S. customer service website has gone down for a third time this week, according to a blog post from Walmart, which did not say why it has taken so long to fix the problem.
The blog post, published on Friday, said that while the outage occurred on Tuesday, the outage has been ongoing since Friday.
In a statement on Twitter, Walmart said it is investigating the outage.
“We are working closely with our customers and the public to resolve the issue,” the statement said.
Walmart customers in the United States are still able to log on to the store using their existing credentials.
It was not immediately clear what caused the outage, or how long it would last.
Earlier this month, the online grocery retailer announced it was shutting down its U.K. online store in the wake of Brexit.
Walmart’s website has been unavailable for several days in the U.KK, where customers can now only use their existing login credentials.
Walmart is the second major U.SK retailer to be shut down due to Brexit, following Ikea, which shuttered its UK stores in February.