CEO of Airtel Payment Bank Anubrata Biswas played down concerns on the future prospects of the service, Hindu Business Line reported, as its parent company released widening loss figures for the unit.

Speaking at finance conference FIBAC, Biswas said payment banks, which provide saving services aimed at unbanked and underbanked communities, remained a “very viable model” but required scale to be successful.

The comments come as Bharti Airtel financial reports on the performance of subsidiary companies revealed the service made a pre-tax loss of INR3.39 billion ($47 million) in its financial year ended March 2019. This loss widened from INR2.73 billion in the previous financial year.

After initial success with the service Airtel faced a significant challenge in November 2017 when it fell foul of rules set out by regulator Reserve Bank of India and was prevented from signing-up new users for seven months.

Since Airtel launched the country’s first Payment Bank service in January 2017, a number of rival services have come to market with mixed fortunes.

Paytm’s version was also briefly suspended from new sign-ups after reportedly breaking RBI customer date rules, though it has since talked-up the progress of its service. Last month the newly integrated Vodafone Idea announced it would abandon its service completely.