Form button for two forms

Recently need line up two form submit buttons for two different forms. So I asked Copilot and Gemini. also the perplexity.

Here are the results:

Copilot:

<form>
    <!-- Form 1 content -->
    <button type="submit" formaction="/action_one">Submit Form 1</button>
    <!-- Form 2 content -->
    <button type="submit" formaction="/action_two">Submit Form 2</button>
</form>

Gemini:

<form action="form1_action.php" method="post">
  <input type="submit" value="Submit Form 1">
</form>

<form action="form2_action.php" method="post">
  <input type="submit" value="Submit Form 2">
</form>

Perplexity: - no two forms
<form action="/DEFAULT_URL" method="post">
  <!-- Input fields here -->
  <button type="submit">BUTTON 1</button>
  <button type="submit" formaction="/URL2">BUTTON 2</button>
</form>
So looks not what I want, or I did not prompt properly? Any way, what I want is:
<form ...>
    ...
    ...
    <button ...>Save</button>
    <button form="back-form"...>Back</button>
</form>
<form id="back-form" ...></form>
sighing...