Changing Status of Shareholders

We are a family owned Private Limited company with 99.96% shareholding (3 Shareholders combined 9996 shares). There are 2 other shareholders owning 2 shares each (Total 4 shares). I am trying to simplify the company working

- How do I remove these two shareholders with 4 shares? They don't want to sell these shares. What are our options in the act to take these 4 shares back from them?

- How do we change these 4 shares to non-voting class of shares? Is there any option in the act to do that?

Any guidance is appreciated on our options.