I refer to the Forum letters by the Infocomm Media Development Authority (TPG has assured IMDA it will resolve customer service issues, Sept 17) and TPG (TPG customer's phone did not support voice service on 4G network, Sept 17).

My experience as a TPG senior subscriber (with two lines) to date has been far from satisfactory, particularly with voice calls.

The use of TPG's 4G Voice app for normal call functions, both incoming and outgoing, has frustrated me for two months now.

What good is a telco when basic voice calls do not always work, even when there is data connection? The app hangs intermittently and has to be restarted.

Even voice calls to and from landlines face similar problems. Isn't the TPG 4G Voice app designed to work with phones that do not support Voice over Long Term Evolution or VoLTE technology?

If gaining market share is pursued at the expense of quality, then a telco falls short of reliability and customer service standards.

Why roll out a service without first resolving compatibility issues and system robustness?

Solutions must be found soon to eliminate or reduce these issues. Standard e-mail replies to queries and setting up more customer hotlines won't work.

What is badly needed are technical and system solutions to address and solve these problems immediately, and this has to include all relevant stakeholders.

Peter Wong Leong Thong