Coles’ Facebook and Twitter accounts were flooded with exasperated messages from customers, after IT maintenance over the weekend caused the supermarket’s website to crash.

The outage, which Coles attributed to a software issue, lasted three days before being resolved on Tuesday afternoon.

“Coles Online is now back up and running and customers can place orders with delivery slots available from tomorrow afternoon,” a Coles spokesperson told Inside Retail on Tuesday.

“We would like to thank our customers for their patience as our IT team worked to fix the software issues impacting the site and apologise for any inconvenience caused by the outage.”

The supermarket giant offered customers with Flybuys accounts who were impacted by the outage a $15 voucher to buy products in stores.

But this left many consumers who did not receive a voucher frustrated, and they vented on social media.

The supermarket giant said it has also been dealing with online trolls who have created fake customer service accounts answering shoppers’ complaints.

On Monday, Coles said it has a new strategy involving an improved online offering. Its online sales grew 27 per cent in Q3 and exceeded $1 billion on a 12-month basis, which the supermarket attributed to its focus on e-commerce and click-and-collect.

This story first appeared on sister site Inside FMCG.