PayPoint has fixed the problem that left up to 1.4 million Brits without gas and electricity.
Parents said they were left struggling to feed their children as freezers defrosted and electricity went down, leaving customers furious on social media.
But now PayPoint has confirmed on their Twitter account the problem has been resolved.
They said: 'We're really sorry for any inconvenience caused to any of our customers today. We have been working hard to fix the problem and we are now pleased to say the service is back to normal. We hope you enjoy the rest of your weekend.'
Customers took to social media earlier today to complain when the system was down.
One person on Twitter said: 'Need to sort this out, not easy when you've had no electric since half 10 this morning and you've got a 6 year old and 11 week old.'
Another said: 'Been to several retailers who have advised your network is down. When will it be back?'
One person added : 'Baby's going without feeding and disabled people being left not being able to top up.'
And another wrote: 'When are the services going to be fixed. I'm on 36p emergency cant afford to lose all my food don't get paid for another week if it all goes off.'
But Keith Robertson said rebooting the terminal had worked, saying: 'Anyone having trouble topping up at PayPoint try going now because my partner was able to top-up our electricity key 10 mins ago!
'Ask them to reboot the system if they say it's still not working - best of luck.'
Another user had an alternative solution, saying: 'If you can call around and find a shop with an older model machine, it should work - on the 4th shop I was able to top up! Good luck to anyone struggling.' A recorded message from the company earlier in the day said: 'We are currently experiencing a nationwide outage with our PayPoint One devices.
'We are investigating the issue and apologise for the inconvenience caused.
'Please reboot your terminal every half an hour until the issue is resolved. Thank you for your patience.'
The company did not say how soon the problem was likely to be resolved.
The service is available at 29,000 locations across the UK, PayPoint's website says, allowing customers to make bill payments in stores around the country.
The company says it handles 818 million transactions annually with hundreds of clients accepting payments through the PayPoint One platform.