Custom Fields in the Cart or Checkout of Dawn theme

[Adam_Bell]

I'm trying to add a "How did you hear about us?" field in the cart. Pretty sure I can't do it at checkout unless I have Plus. I tried adding a HTML select menu to the main.cart.items.liquid section, but it just throws an error.

This is the code I'm using right after the closing table element:

          <label>How did you hear about us?</label><br>
  <select id="how-did-you-hear-about-us" name="attributes[How did you hear about us?]">
    <option value="Email"{% if cart.attributes["How did you hear about us?"] == "Email" %} selected{% endif %}>Email</option>
    <option value="Phone"{% if cart.attributes["How did you hear about us?"] == "Phone" %} selected{% endif %}>Phone</option>
    <option value="In Person"{% if cart.attributes["How did you hear about us?"] == "In Person" %} selected{% endif %}>In Person</option>
    <option value="From a Friend"{% if cart.attributes["How did you hear about us?"] == "From a Friend" %} selected{% endif %}>From a Friend</option>
  </select>

[paramountariana]

I am having the same issue with the same theme. I used third party app SmartCA: Customer Attribute.

Hope that helps.