Submit button not rendered

Hello,

I have a small contact form with a peculiar problem- the submit button HTML is not rendered unless I precede it with button element.

This example renders code and displays the submit-

<label class="required">Fields with an * are required.</label>

<label>Name*</label> [text* p_name]

<label>Company Name*</label> [text* c_name]

<label>Phone Number*</label> [text* p_number] 

<label>Email*</label> [email* email]

<label>Subject*</label> [text* subject]

<label>Message:</label> [textarea message]

<label>Help us fight SPAM!</label> [quiz quiz-179 8/2 "7-3=|4"]

<label></label><button type="button" style="display:none">Submit</button>[submit "Submit"]

However if I remove the hidden button element the HTML for the submit is not rendered. This is not a display issue, not CSS. The HTML for the submit button is not present.

Also tried adding a test text field after the button code with same issue- no submit.

Has anyone encountered this?

https://www.ads-software.com/plugins/contact-form-7/