Marks & Spencer has been forced to stop taking online orders following a cyber attack.
The retail giant has paused orders on its website and apps since Friday as it attempts to restore operations.
Customers began reporting problems last weekend - with people struggling to use contactless payments, click & collect, and gift cards - and on Tuesday the retailer confirmed it was facing a "cyber incident".
Then on Friday M&S said it was pausing taking orders through its UK & Ireland websites and apps and some international websites.
It apologised for the inconvenience and said it would refund orders placed by customers on Friday.
M&S says contactless payments are now working and gift cards can be used.
M&S's sales and profits have improved in recent years and it has been seeking to expand its online operations.
Last year, out of £3.9billion of sales in its clothing and home business, nearly £1.3billion came online.
With warmer weather due this week, and shoppers turning their thoughts to summer, analysts said M&S could be missing out on sales at a critical time, as people were likely to turn to rival retailers to get what they want.
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