QuickBase API AddRecord Call

Hey, folks.
I'm a bit new to QuickBase so, if I'm making a beginner's mistake in not understanding what I'm missing, please forgive.
As you can tell by the title I'm testing the api call AddRecord via Postman.
This is what I'm request looks like:

<qdbapi>
  <usertoken>MyUserToken</usertoken>
  <field name="Last_Name">My Last Name</field>
  <field name="First_Name">My First Name</field>
</qdbapi>​

I'm sending my POST request to https://myurlname.quickbase.com/db/DBID (obviously not the real URL)
with headers 

Content-Type: application/xml

QUICKBASE-ACTION: API_AddRecord​

This is what I'm expecting as a response:

<qdbapi>
 <action>API_AddRecord</action>
 <errcode>0</errcode>
 <errtext>No error</errtext>
 ...
</qdbapi>​

But I'm getting this:

<qdbapi>
 <action>API_AddRecord</action>
 <errcode>2</errcode>
 <errtext>Invalid input</errtext>
</qdbapi>​

------------------------------
Dowen Robinson
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