ActionController::UnknownFormat After Rails 7 Upgrade

I have a calculator which users would enter in values, hit submit and without refreshing or re-rendering, the calculated values would display on the page. All worked well until I upgraded from Rails 6.1.4.6 to 7.0.2.2. Now I receive this error below:

When I add format.html to the respond_to block, I get this error:

When I add format.html { render :new } to the respond_to block, the page re-renders the new.html.erb file but without calculated values (i.e create.js.erb file is not running).

Any help would be appreciated.

Here are the files that ran perfectly in Rails 6.

calculator_controller.rb

def create
  @calculation = calculate_one_option

  respond_to do |format|
    format.js
  end
end

def new; end

new.html.erb

<%= form_tag calculate_path, method: :post, remote: true do %>
  ... form stuff ...
  <%= submit_tag "Calculate" %>
<% end %>

create.js.erb

var formatter = new Intl.NumberFormat('en-US', { style: 'currency', currency: 'USD' });

if ("<%= @calculation.error %>".length > 0 ) {
  alert("<%= @calculation.error %>");
  ... js stuff ...
} else {
  ... more js stuff ...
}