First Name is not collected

Hi there,
I have formed a custom sign-up form but unfortunately the first name is not collected while the subscription works in general.
I have used the sendpress form generator – first and last name won’t be collected there too.
How can I fix this?

<form method="post" action="https://www.enter-utopia.com/">
	<input type="hidden" name="sp_list" value="3005"/>
	<input type="hidden" name="sendpress" value="post"/>
          <div class="form-row justify-content-center">
            <div class="col-auto"><label for="email">
<input class="sp_firstname required" class="form-control" type="text" placeholder="Enter your First Name" name="sp_firstname" /></label>
            </div>
            <div class="col-auto">
<input class="sp_email required" class="form-control" type="text" placeholder="Enter your Email" type="email" name="sp_email" />
            </div>  
<div class="col-auto">
<input value="" class="sendpress-submit" type="hidden" id="submit" name="submit">
            <button type="submit">Subscribe</button>
            </div>
          </div>
        </form>

Any suggestion/hint?

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