UK clothing maker and retailer SuperGroup has warned investors it will be between £6 and 9 million less profitable than expected this year, following issues with an upgrade to its warehouse management system.

The company’s share price dropped 29% following the profit warning.

"At the end of August SuperGroup implemented an upgrade programme to its warehouse management systems to increase capacity and efficiency at its Barnwood site to meet future growth in demand," the company said in a statement.

"Once live, the business encountered some short-term issues in the transition which has caused a significant, temporary reduction both in the amount of stock and range of sizes reaching its UK stores," it said.

SuperGroup has commissioned temporary warehousing facilities in order to house the extra £2 million-worth of stock it has failed to ship.

"Whilst the majority of the system issues have been rectified, some are still ongoing," the company said. The impact on its supply chain will persists until November.

Last month SuperGroup announced a strong set of results for the most recent financial quarter. Sales grew 66% year-on-year, and the company opened two new stores in the UK despite "a difficult retail market".

The company, which appointed a new group head of IT earlier this year, had worked with an IT consultancy called Retail Answers to develop "an IT plan to meet the exceptional growth of the organisation".

Neither Retail Answers or SuperGroup would provide Information Age any more information about the system in question.