The deadline for Live 8 ticket winners to claim their place at next month's concert has been extended after nearly 2,000 people failed to reply.
Tickets were allocated after a text message competition
Organisers put back the closing date by one day until 1200 BST on Tuesday to give the missing winners more time.
More than 2m sent text message bids for 150,000 tickets. The winners were notified by text message on Thursday.
A spokesman urged outstanding winners to visit the Live 8 website to arrange the collection of their tickets.
The spokesman said that all tickets for the Hyde Park show to fight African poverty had to be collected from mobile phone firm O2's shops "by close of business on 27 June".
He said: "We have had an overwhelming response with people registering and redeeming their tickets. However, less than 2,000 people are still yet to register to claim their tickets."
Any unclaimed tickets would be reallocated by the organisers, he added.
The text contest earned a place in the Guinness World Records as the world's largest text message lottery.
It raised £3m - with part of the money covering the cost of staging the concerts.
The concerts will attempt to put pressure on world leaders to forgive African debt and increase aid budgets at the G8 summit near Edinburgh.
Live 8 organiser Bob Geldof spoke out after scores of pairs of tickets for the concert - featuring acts like U2 and Coldplay - went up on eBay within hours of the text competition ending.
The auction site removed the ticket listings last Tuesday, saying it was "listening to customers".