NatWest became the second financial institution to report technical problems on Thursday after up to 2m Nationwide transactions were duplicated reports The Telegraph. An RBS spokesman said: "Online banking is now fully operational and debit card transactions are processing as normal. We continue to monitor the systems closely and will keep our customers fully informed. We apologise for any inconvenience caused." Earlier in the summer, Natwest suffered a major systems collapse when millions of customers were unable to check their balances, withdraw cash or make payments. NatWest promised that no customers would be left out of pocket as a result of the technology problems. Although it has not yet been revealed what caused the problems at RBS, the Nationwide issue was attributed to "human error" and meant some customers who used their Visa cards on Tuesday had duplicate payments also taken out on Wednesday.