Excise tax for all 3 Giant Mobile Phone Service Providers for the SMS Services

The government has still no capability to monitor the traffic of the SMS in the nation. The National Telecommunications Commission (NTC) allegedly does not know how many SMS exactly being sent and it would be difficult for them to know the exact profit of the heavy players like Smart, Globe, and Sun.
Excise tax per SMS is being pushed by the government however the 3 giant companies are finding ways and excuses to avoid this.
In my personal point of view the government should find ways to keep track the SMS being sent by subscribers and get the appropriate tax from it. I hope there are alternative ways to keep track the income of these service providers.