Use of a variable in a snippet

For a form in different languages (but not an multilang website) I use blueprints with the form label names for the different languages. In general the website has only one language.

I’ve a snippet for a input field:

<label for="<?= $field ?>" class="form-label">
<input class="form-input" type="text" name="<?= $field ?>" value="" required>

And in the template I want to use this for every input field:

<?php snippet('forms/input', ['field' => 'first_name']) ?>

In the blueprint for the english form:

first_name: First name
last_name: Last name


The same for the other languages.

Now I would like to get the label name LABEL in the Snippet.

When I try to use this code for LABEL (see above):

<?= $page->content()->get('first_name')->html() ?>

I get the corret label, but when I use it with the variable:

<?= $page->content()->get($field)->html() ?>

…It doesn’t work…

How is the right way to solve this?
The labels don’t have to be in the blueprint, but this way it would be possible to be edited in the panel…

I’m sorry… It was a simple typo mistake in the variable name (firstname vs first_name)… the code is correct…