On Sunday, NOVA subscribers were unable to receive phone calls or messages originating from other service providers, according to a statement made by the company.
NOVA explained that there was a malfunction, and that the problem was temporary.
Subscribers throughout many regions in Greece reportedly claimed that they were impacted by the service failure.
NOVA is a member of the United Group, which is a telecommunications and media group in southeast Europe. It offers a wide range of services such as mobile and landline telephony services, internet, subscription television programming called EON TV, and, according to its website, services over five million subscribers.