The NOS mobile phone operator suffered system failures and service interruptions on Sunday afternoon, nationwide.
The company’s management said on Sunday that full service will be resumed by 9pm.
The telecoms operator said, "There was a mid-afternoon network failure that affected some customers who had an intermittent voice service, but it is being resolved."
Of the approximately 4 million fixed telephone network users, around 37% are NOS customers. Of the 12.3 million mobile phone customers, 24.7% are from NOS, according to a report by the National Communications Authority released in January 2019.
The NOS communications operator resulted from the 2013 merger of ZON Multimédia and OPTIMUS Telecomunicações.
