Third button in ionic select

I am trying to add a third button in ion-select,

We alreay have buttons like okay and cancel…
I looked into ion-select docs and I tried to use alertOptions for third button

 this.alertOptions  = {
      cssClass: 'accepted-payments',
        text: 'none',
        handler: () => {

So neither did it add the cssClass to ion-select nor there was extra button. but It worked for title and subTitle value changes

There are also some instance members metion in alert docs with methods like addInput and addButton . but how do I use them with ion-select?

Any idea anyone? Thanks in advance.
Or can it be done in some other way?

did you find a solution? the docs still state that alert options work, but it seems to ignore the button array