Understanding the Situation
I understand the situation of Siva like this: the workers of the company have formed a trade union, and the management wants there to be no trade union. Therefore, the management wants to know if they can cancel the trade union registration.
Now, as Umakanthan Sir has said, the employer has no role to play in it. There is no need for the employer to give permission to form a union. If a no-objection certificate from the management is required to form a trade union, then I don't think we will have any trade union! Will any employer give permission to the workers to form a trade union? No, not at all. Therefore, that issue is totally rejected.
Changing the Minds of Trade Union Members
Coming back to what Umakanthan Sir has said, you can consider something that can change the minds of the trade union members, leading them to resign from membership and dissolve the trade union.
The Reality of Trade Unions
Regarding the real scenario, I would say that a trade union is a fact wherever workers are discontent. It indicates that the management is not employee-friendly or approachable. Therefore, if they have formed a union, let them continue to seek the union's assistance. In my experience, trade unions are always good for maintaining smooth industrial relations. You need to negotiate with the union and seek their assistance whenever required. Don't view it as a platform to defend, but as an opportunity to negotiate, correct, and build relationships.