In an external webpage that I do not administrate, I have to fill a form that has no id or name. The "submit" button code looks like this:

<button type="submit" class="sui-AtomButton sui-AtomButton--primary sui-AtomButton--solid sui-AtomButton--center">
  <span class="sui-AtomButton-inner">Save</span></button>

At first I tried a simple click like this:

await.page.click('[type="submit"]')

The button was clicked but it did not trigger the submition of the form (I also tried using "Enter" with the keyboard, but the result is the same).

Then, I tried to trigger the submit from the own form like this:

await page.evaluate(() => {
      
 document.forms[0].submit();

})

and like this:

await page.evaluate(() => {
 
 var f = document.forms[0]
 Object.getPrototypeOf(f).submit.call(f);

})

and also like this:

await page.evaluate(() => {
      
 document.forms[0].submit(function(event){
   event.preventDefault();
 });

})

In all the three cases the result is an error in the page.

What should I do? Thanks in advance.