Hello,
I guess there is an script in your webpage that is removing the special tag: <div id="cp_subbtn_1" class="cp_subbtn" style="display:none;">Calculate</div>
with the submit button. So, I recommend you emulate the submit button with a common button field. Please, insert a button field in the form with the following piece of code as its onclick event:
jQuery(this).closest('form').submit();
To modify its appearance, enter a custom class name through the attribute: “Add CSS Layout Keywords” in the field’s properties, for example: my-submit, and then enter a style definition similar to the following one:
#fbuilder .my-submit input{background:#FF0000;}
Through the “Customize Form Design” attribute in the “Form Settings” tab (https://cff.dwbooster.com/images/documentation/form-settings-tab.png)
Best regards.