Nepal Telecom’s (NT) prepaid mobile phone services were disrupted across the country on Wednesday due to a sudden problem in the server.

The NT system room in Sundhara encountered the hitch which led to phones going dead for around one and a half hours.

Apart from voice and data services, the problem in the server also affected the billing system. NT said that connections between prepaid and postpaid, prepaid and landline and prepaid and prepaid phones were cut off. “The system room where the server was installed started becoming hot. As a result, the server went down,” said Buddhi Prasad Acharya, managing director of NT. “We responded to the problem immediately and got the system back online within an hour.”

There is air conditioning in the system room to prevent equipment from heating up. Officials suspect the problem occurred due to a breakdown in the air conditioning.

Though Acharya claimed that NT’s service was up and running within an hour, an observation carried out by the Post showed that the system did not function till late evening. As per NT’s claims, the service went down at around 2:15 pm and lasted till 3:30 pm.

According to NT, since the problem had been unexpected and the company was not able to deal with it immediately, it took some time to reload the server.

The data of the Nepal Telecommunications Authority (NTA) shows that there were 13,244,356 subscribers of its voice telephony service as of mid-September 2015. Of the total, there are 11,156,138 subscribers of GSM service. The data also reveals that NT shares the leading spot in telecommunication services with Ncell. The two companies have a market share of 46 percent each.

“We received a number of complaints regarding cross-network connections. After making a study, we found out that the problem had occurred due to some problem in NT’s system,” an Ncell source said. “The company had received hundreds of complaint calls.”

Moreover, congestion in the system remained high as people made repeated attempts to make a call. According to the NTA, there are 26.8 million telecom subscribers across the country.